Deck 4: BTA Certified Blockchain Solution Architect

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سؤال
In the Ethereum EVM there are two types of memory areas. (Select two.)

A) Storage
B) Database
C) Memory
D) Persistent
E) Ephemeral
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سؤال
The gas price is a value set by the creator of the blockchain transaction? Select best answer.

A) false
B) Its Negotiable
C) true
سؤال
You currently using the Metamask Chrome plugin and you see a selection for Etherescan in the plugin. What is Etherscan used for?

A) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Ethereum Blockchain
B) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Bitcoin Blockchain
C) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Ethereum and Tokens Blockchain
D) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on any Blockchain
سؤال
Regarding Ethereum contracts, the contracts can call (perform) two specific message calls. The message calls are either _____________ or __________? (Select two.)

A) Bitcoin nodes
B) Send Ether to non-contract
C) DApps
D) Other contracts
E) Ether Nodes
سؤال
Which of the following would NOT be true about what a smart contract gives your organization?

A) Accuracy
B) Savings
C) Autonomy
D) Trust
E) Legal Assurance
سؤال
A ____________cipher basically means it is using a fixed key which replaces the message with a pseudorandom string of characters. It is basically the encryption of each letter one at a time. What is the cipher type?

A) Stream
B) Block
C) Parallel
D) RSA
سؤال
In the EVM every account has a persistent key-value store mapping 256-bit words to 256-bit words called ________

A) Gas
B) Space
C) Storage
D) Datastore
E) Database
سؤال
Contracts live on the blockchain in an Ethereum-specific binary format called _____________?

A) EOS
B) EVM Code
C) Ether
D) Gas
E) EVM Bytecode
سؤال
You are considering writing smart contracts and there are a few different languages you can consider. (Select two.)

A) Truffle
B) Serpent
C) Solidity
D) Embark
سؤال
Secure Hash Algorithm (SHA-256) output is always 256 bits or 32 bytes in length regardless of the length of the input (even if input is millions of bytes). Select best answer.

A) NSA is spying on us so what's it matters.
B) Depends on input
C) false
D) true
سؤال
Which of the following blockchain is NOT a permissioned blockchain?

A) Quantum
B) Ethereum
C) R3 Corda
D) Ripple
E) Hyperledger
سؤال
What blockchain is considered Blockchain 1.0, the first blockchain?

A) Bitcoin Cash
B) Ethereum
C) Litecoin
D) Bitcoin
E) NEO
سؤال
The key difference between encryption and hashing is that encrypted strings can be reversed back into their original decrypted form if you have the right key?
سؤال
Vitalik Buterin referred to this concept of trust beyond just currency as 'smart contracts' or even blockchain-based "decentralized autonomous organizations" (DAOs). Ethereum is considered Blockchain version?

A) 2.0
B) 4.0
C) 3.0
D) 1.0
سؤال
In the Bitcoin blockchain the "block creation time" is set to 10 minutes and this can never change.
سؤال
What type of attack would be considered a very large flaw in public blockchains such as Bitcoin's Blockchain where the majority of hashpower could possibly be controlled thru an attack? What is the specific attack Bitcoin could be exposed to?

A) 51% Attacks
B) Tether Token Hack
C) DDoS Attack
D) BIP attack
E) Parity Wallet Attack
سؤال
R3 Corda does not organize time into blocks. What does Corda actually perform and use? <strong>R3 Corda does not organize time into blocks. What does Corda actually perform and use?  </strong> A) Ripple is implemented as the blockchain and XRP for cryptocurrency. B) Notary services and timesmapping C) R3 Corda is a blockchain and does use blocks D) Notary services and timestamping <div style=padding-top: 35px>

A) Ripple is implemented as the blockchain and XRP for cryptocurrency.
B) Notary services and timesmapping
C) R3 Corda is a blockchain and does use blocks
D) Notary services and timestamping
سؤال
What are two cryptocurrencies that you would expect to see mining equipment with ASICS? (Select two.)

A) Bitcoin
B) Ethereum
C) Neo
D) Litecoin
E) Monero
سؤال
The___________________ is the runtime environment for smart contracts in Ethereum?

A) Metamask
B) Ether
C) Mist
D) EVM
سؤال
Ethereum is considered to be a ______________type of blockchain.

A) Permissionless
B) Permission Based
C) Hybrid
D) Private
سؤال
Which of the following is NOT considered a token?

A) ICON
B) LTC
C) Golem
D) EOS
سؤال
______________is supposed to be the constant cost of network resources/utilization in the Ethereum blockchain? What is the constant?

A) Wei
B) Tether
C) Gas
D) Ether
سؤال
The Hyperledger Fabric business network is divided into three categories. What are the three categories? (Select three.)

A) Membership
B) Chaincode
C) Networking
D) EVM
E) Blockchain
سؤال
You are using Truffle for an Ethereum contract and would like to use a default set of contracts and tests from within an empty project directory. What is the syntax?

A) truffle defaults
B) truffle init
C) truffle test
D) truffle compile
سؤال
Every node needs to keep track of time AND it needs to be in synch with its other peer nodes on the blockchain. In Bitcoin for example the current median for time is around?

A) 7 minutes
B) 7 seconds
C) 17 seconds
D) 70 Minutes
E) 70 Seconds
سؤال
Ethereum has a metric system of denominations used as units of ether. What is the smallest denomination of Ether?

A) Kwei
B) Shannon
C) Wei
D) Finney
سؤال
Which of the following is NOT a requirement of an enterprise blockchain typically?

A) Append-only distributed system of record shared across business network
B) Cost efficient blockchain
C) Transactions are endorsed by relevant participants
D) Ensuring appropriate visibility; transactions are secure, authenticated & verifiable
سؤال
In Hyperledger Fabric, the smart contract logic is also called by two other names _______________ and ______________? (Select two.)

A) CordApps
B) DApps
C) Programmatic Logic
D) Ripple
E) Chaincode
F) Ledger
سؤال
Which of the following enterprise blockchains have a pluggable framework consensus algo? (Select two.)

A) Quorum
B) R3 Corda
C) Ethereum
D) Hyperledger Fabric
E) Ripple
سؤال
The block creation time is set to how many minutes in Bitcoin? 

A) 1
B) 10
C) 120
D) 100
E) 15
F) 150
سؤال
You have flown to NYC to have a discussion with a technical executive of a too big to fail bank. You are having a discussion about blockchain algos and the customer is asking what are some disadvantages of using a POW algo?

A) Centralization of blockchain control
B) Only use case for computational power is blockchain
C) Large expenditures for computational power
D) Not profitable for miners
E) 51% attack mitigation
سؤال
How many peers in the network need to endorse a transaction in a Hyperledger Fabric blockchain?

A) The number of peers required to endorse a transaction is driven by the IAM policy that is specified by the ledger.
B) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified by the DApps.
C) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified by the ledger.
D) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified at chaincode deployment time.
سؤال
You are using Geth and you would like to list the accounts controlled by the node. What is the command?

A) geth list accounts
B) geth account node list
C) geth account node
D) geth account list
سؤال
Which of the following blockchain key components state how the transactions will be confirmed?

A) Distributed Ledger database
B) Validity Rules
C) Consensus Algorithm
D) Encryption
سؤال
What is diagram referencing below? <strong>What is diagram referencing below?  </strong> A) AND Gate B) XOR Gate C) OXR Gate D) NAND Gate <div style=padding-top: 35px>

A) AND Gate
B) XOR Gate
C) OXR Gate
D) NAND Gate
سؤال
You are trying to generate a random number in Ethereum blockchain. What is the best way?

A) Wikipedia
B) Coindesk
C) Coinbase
D) Randao
E) ERC20
سؤال
What are two reasons that you would consider implementing a POW algo in your blockchain? (Select two.)

A) PoW imposes no limits on actions in the network and therefore can thwart attacks better than other algos due to high cost
B) What matters is to have large computational power to solve the puzzles and form new blocks over having a financial stake.
C) PoW imposes some limits on actions in the network and therefore can thwart attacks better than other algos due to high cost
D) The algo is energy efficient compared to POS and BFT
E) The algo is energy efficient compared to POS and DPOS
سؤال
When considering tokens on the Ethereum Blockchain what is the main difference between ERC20 and ERC721 tokens?

A) No difference on Ethereum all tokens are fungible
B) ERC20 is not fungible while ERC721 tokens are fungible
C) ERC721 is not fungible while ERC20 tokens are fungible
D) No difference on Ethernet all tokens are not fungible
سؤال
Gas has multiple associated terms with it: Gas Prices, Gas Cost, Gas Limit, and Gas Fees. The principle behind Gas is to have a stable value for how much a transaction or computation costs on the Ethereum network. Which is considered to be the static value for how much a computation costs in terms of Gas?

A) Price
B) Fee
C) Cost
D) Limit
سؤال
Is it possible to access the blockchain via an Ethereum Node?

A) Yes
B) No
سؤال
The CA (Fabric CA by default) issues a ______________ to each member (organization or individual) that is authorized to join the network.

A) rootCert
B) tCert
C) eCert
D) NodeCert
سؤال
In Ethereum a block contains two very important parameters. (Select two.)

A) Difficulty
B) Release date
C) Block number
D) Timestamp
سؤال
Select the best statement for determining how consensus is reached.

A) By the miner nodes which make sure that a transaction is valid.
B) By a cryptographic secure signature algorithm called ECDSA which makes sure that cheating is impossible.
C) By every single node in the blockchain network different transactions.
D) By every single node in the blockchain network executing the same transaction.
سؤال
What is provided by the Hyperledger Fabric to facilitate network communications?

A) API
B) SDK
C) Ruby
D) Middleware
سؤال
Composer Modeling Language is an object-oriented modeling language that defines the domain model for a business network definition. The modeling language is saved as a __________ file.

A) .json
B) .go
C) .txt
D) .ico
E) .cto
سؤال
When developing in Ethereum which is considered to be an In-Memory Blockchain simulations for rapid development?

A) Cpp-ethereum
B) Geth
C) TestRPC
D) Parity
سؤال
In regards to understanding the Ethereum Virtual Machine what statement is true?

A) The EVM is extremely powerful, non-turing complete and perfect for doing computational intensive thins, because of the direct access to the graphics card.
B) The EVM is extremely powerful, turing complete and perfect for doing computational intensive things, because of the direct access to the graphics card.
C) While the EVM is Sandboxed, it isn't as powerful as the Bitcoin network, because it's not Turing Complete
D) The EVM can't access hardware layers or anything outside a blockchain node because it's sandboxed.
سؤال
Fabric Ledger has two specific parts. Select answer with the proper two parts.

A) State Data, Transactional Data
B) State Data, Transaction logs
C) LevelIDb, CouchDB
D) Transaction Logs, CouchDB
سؤال
Ethereum currently uses the ___________Consensus Algo and in the future it is planned to go to the __________Consensus Algo?

A) PoW, DPoS
B) PoW, PoS
C) PoS, PoW
D) DPoS, PoW
سؤال
Hyperledger Composer has two main components. What are the two components? (Select two.)

A) Fabric
B) Sawtooth
C) Playground
D) Explorer
E) Business Network Archive
F) SDK
سؤال
Bitcoin implemented Byzantine Fault Tolerance through a system named:

A) Authenticated Encryption
B) Proof of Work
C) PBKDF2
D) None of the above
سؤال
What consensus algo uses a method of sending coins to an address where they cannot be retrieved?

A) Proof of Stake
B) Proof of Activity
C) Proof of Burn
D) Proof of Sending
سؤال
Chaincode Services uses Docker to host (deploy) the chaincode without relying on any virtual machine or computer language. What would be the main reason or best reason that Hyperledger chose containers over virtual machines?

A) Docker provides a secured, lightweight method to sandbox chaincode execution that is not "locked down".
B) Docker provides a secured, lightweight method to sandbox chaincode execution that is not "locked down" but additional programming languages cannot be enabled.
C) Docker provides a secured, lightweight method to sandbox chaincode execution that is "locked down".
D) Docker is fully compatible with Hyperledger and Linux with an upgrade subscription.
سؤال
The fabric framework is implemented on ______programming language. What programming language?

A) Go
B) Python
C) Node.js
D) Java
E) JS
سؤال
Hyperledger can best be described as a ____________________?

A) Blockchain that exclusively supports PoS Consensus
B) Permissionless blockchain
C) Token
D) Blockchain that exclusively supports PoW Consensus
E) Umbrella collaboration of open source blockchains
سؤال
What benefit does HPE Cloud Cruiser provide?

A) Need for proven, production-ready technology
B) Need a full history of all application data
C) Require top-notch performance
D) Need to avoid data duplication or redundancy
سؤال
Which is the right order for Ethereum Denominations?

A) Finney, Szabo, Mether, Wei
B) Gwei, Szabo, Finney, Ether
C) Finney, Szabo, Mether, Gwei
D) Wei, Finney, Szabo, Ether, Tether
سؤال
What is the difference in using Go-Ethereum over Ganache?

A) Can automate builds with Go Ethereum but you can't with Ganache
B) Go Ethereum is written in Java whereas Ganache is written in Golang
C) Go Ethereum is real blockchain whereas Ganache is a blockchain simulation
D) Ganache is a real blockchain whereas Go Ethereum is a blockchain simulation
سؤال
When you are developing with Fabric Composer which of the following is true?

A) Decreases the time of development
B) Simplifies the development of applications
C) Simplifies the integration of client applications
D) Increases the time of development
سؤال
In what year did a whitepaper that was published by "Satoshi Nakamoto" outlined a solution to the Byzantine Generals problem?

A) 2006
B) 2009
C) 2008
D) 2010
سؤال
How does a client app communicate with Hyperledger fabric chaincode (Smart Contracts)?

A) The app uses an SDK which invokes functionality on the chaincode which then announces the transaction to any peers required to endorse the transaction
B) The app uses Hyperledger Composer to communicate with CouchDB which in turn invokes chaincode functionality
C) Client apps don't communicate with Hyperledger fabric directly, they must use Hyperledger Composer for the transmission
D) The app points to a node's IP address, then calls an invoke function on the chaincode address to start the write process
سؤال
On the Ethereum blockchain the "nonce" of a transaction:

A) Holds the gas amount to be paid to the miner writing the block that contains the transaction
B) Is used to ensure that transactions by a given account are written in sequential order
C) Is reset to zero after each successfully mined blocked
D) Must always start with four zeroes
سؤال
Blockchain systems assume all parties are trusted by all other parties in the exchange or ecosystem.
سؤال
To interact with a deployed Ethereum Smart Contract, a user or app must:

A) Have a reference to the public address of the deployed Smart Contract
B) Have the appropriate permissions needed to invoke the functions of the Smart Contract
C) Have sufficient gas to perform read and write operations against the Smart Contract
D) All of the above
سؤال
Which of these is the name of a well known open source peer-to-peer hypermedia distributes file system?

A) FileBlocks
B) Hyperbole
C) FileDropper TM FileDropper TM
D) IPFS
سؤال
By design, permissioned blockchains such as Hyperledger Fabric are not capable of creating or utilizing cryptocurrency.
سؤال
What does the acronym DAO represent?

A) Distributed Autonomous Operations
B) Distributed Anonymous Organization
C) Distributed Anonymous Operations
D) Decentralized Autonomous Organization
سؤال
If a Proof of Work blockchain such a s Bitcoin or Ethereum changed to a Proof of Stake consensus paradigm, which key component of the Proof of Work process would be eliminated?

A) There would be no need for the miners or nodes to perform a guessing game
B) The need to solve Byzantine Fault Tolerance
C) All fees related to transactions would be removed
D) The blockchain network would no longer have to display public transactions
سؤال
Adding more nodes to a blockchain network has which effect?

A) Increased centralization
B) Increased security
C) Decreased costs
D) Increased performance
سؤال
Which of these reasons is a good reason to choose a conventional database over blockchain to store application data?

A) Centralization is to be avoided
B) Databases should never be used over blockchain
C) Full history is needed for all data
D) High performance is required
سؤال
One critical business consideration you must account for when choosing Hyperledger Fabric over Ethereum is:

A) Who you will have host the nodes and how will you deploy the network
B) If your blockchain will use Proof of Work or Proof of Stake
C) Which cryptographic algorithms Hyperledger Fabric employs
D) How you will implement your own gas/fee system
سؤال
Which of the following scenarios and databases is least suited to be utilized by a blockchain solution?

A) Scenario: Law enforcement system; Dataset: Criminal Arrests, Warrants for Arrest, Conviction Date
B) Scenario: An Email campaign service; Dataset: Recipient Email, From Email; Subject, Body
C) Scenario: A family filter wifi router; Dataset: Websites Visited, Websites Blocked, Download History
D) Scenario: Credit score app; Dataset: Credit Score, Hard Inquiries; Collections, Date Removed, Date Added
سؤال
Proof of Stake based blockchain systems use what design to permit valid write transactions?

A) A genesis "Stake" node approves or disapproves transactions announced from other nodes
B) Validator nodes each give or pay a stake in order to write transactions, and if malicious, will lose their stake
C) Stakeholders or early product investors host nodes that approve or disapprove transactions from other nodes
D) Every node on the network holds an equal stake, and if malicious, gets flagged for removal
سؤال
The word "Drapp" or "DApp" is most commonly understood to mean what?

A) Distributed Application
B) Distributed Apps and Programs
C) Decentralized Application
D) Distributed Autonomous Application
سؤال
Public blockchains can alter the blockchain ledger by:

A) Creating a hard fork of the blockchain data, tooling and/or software
B) Achieving community consensus via a Smart Contract to update the ledger
C) Re-hashing the blocks from the total block height down to the genesis block
D) Blockchain ledgers are immutable and can never be altered
سؤال
Which of these technical components best represents why cryptocurrency is able to operate successfully?

A) An immutable digital ledger that is validated and distributed across many peers
B) Using API calls, cryptocurrency having a direct correlation to USD exchange rates
C) High performance computing power allows cryptocurrency to be minted just as a central government might do with fiat currency
D) Blockchain cryptocurrency transactions are always public which generates user trust and adoption
سؤال
The first actual known blockchain software implementation and deployment occurred:

A) In 1991 by Stuart Haber
B) In 2011 Markus Persson
C) In 2009 by Satoshi Nakamoto
D) In 1991 by Linus Torvalds
سؤال
Which factor influences the gas cost to deploy a Smart Contact on the Ethereum blockchain?

A) None. Smart Contract deployment has a fixed gas cost
B) The types of operations written in code within the Smart Contract
C) The current Ethereum market conditions
D) The total size of the complied Smart Contract measured in kilobytes
سؤال
Blockchain systems can offer what advantage over centralized systems?

A) They are much easier to maintain and update
B) They have significantly higher transaction speeds
C) Their distributed ledger systems are more secure and immutable
D) All of the above
سؤال
Some of the various consensus models employed by public blockchain networks include:

A) Proof of Work
B) Proof of Importance
C) Proof of Stake
D) All of the above
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ملء الشاشة (f)
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Deck 4: BTA Certified Blockchain Solution Architect
1
In the Ethereum EVM there are two types of memory areas. (Select two.)

A) Storage
B) Database
C) Memory
D) Persistent
E) Ephemeral
A,C
2
The gas price is a value set by the creator of the blockchain transaction? Select best answer.

A) false
B) Its Negotiable
C) true
C
Explanation: The gas price is a value set by the creator of the transaction, who has to pay gas_price * gas up front from the sending account. If some gas is left after the execution, it is refunded in the same way. If the gas is used up at any point (i.e. it is negative), an out-of-gas exception is triggered, which reverts all modifications made to the state in the current call frame.
3
You currently using the Metamask Chrome plugin and you see a selection for Etherescan in the plugin. What is Etherscan used for?

A) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Ethereum Blockchain
B) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Bitcoin Blockchain
C) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on the Ethereum and Tokens Blockchain
D) A search engine that allows users to easily lookup, confirm and validate transaction that have taken place on any Blockchain
A
Explanation: A search engine that allows users to easily lookup, confirm and validate transactions that have taken place on the Ethereum Blockchain
4
Regarding Ethereum contracts, the contracts can call (perform) two specific message calls. The message calls are either _____________ or __________? (Select two.)

A) Bitcoin nodes
B) Send Ether to non-contract
C) DApps
D) Other contracts
E) Ether Nodes
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5
Which of the following would NOT be true about what a smart contract gives your organization?

A) Accuracy
B) Savings
C) Autonomy
D) Trust
E) Legal Assurance
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6
A ____________cipher basically means it is using a fixed key which replaces the message with a pseudorandom string of characters. It is basically the encryption of each letter one at a time. What is the cipher type?

A) Stream
B) Block
C) Parallel
D) RSA
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7
In the EVM every account has a persistent key-value store mapping 256-bit words to 256-bit words called ________

A) Gas
B) Space
C) Storage
D) Datastore
E) Database
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8
Contracts live on the blockchain in an Ethereum-specific binary format called _____________?

A) EOS
B) EVM Code
C) Ether
D) Gas
E) EVM Bytecode
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9
You are considering writing smart contracts and there are a few different languages you can consider. (Select two.)

A) Truffle
B) Serpent
C) Solidity
D) Embark
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10
Secure Hash Algorithm (SHA-256) output is always 256 bits or 32 bytes in length regardless of the length of the input (even if input is millions of bytes). Select best answer.

A) NSA is spying on us so what's it matters.
B) Depends on input
C) false
D) true
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11
Which of the following blockchain is NOT a permissioned blockchain?

A) Quantum
B) Ethereum
C) R3 Corda
D) Ripple
E) Hyperledger
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12
What blockchain is considered Blockchain 1.0, the first blockchain?

A) Bitcoin Cash
B) Ethereum
C) Litecoin
D) Bitcoin
E) NEO
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13
The key difference between encryption and hashing is that encrypted strings can be reversed back into their original decrypted form if you have the right key?
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14
Vitalik Buterin referred to this concept of trust beyond just currency as 'smart contracts' or even blockchain-based "decentralized autonomous organizations" (DAOs). Ethereum is considered Blockchain version?

A) 2.0
B) 4.0
C) 3.0
D) 1.0
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15
In the Bitcoin blockchain the "block creation time" is set to 10 minutes and this can never change.
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16
What type of attack would be considered a very large flaw in public blockchains such as Bitcoin's Blockchain where the majority of hashpower could possibly be controlled thru an attack? What is the specific attack Bitcoin could be exposed to?

A) 51% Attacks
B) Tether Token Hack
C) DDoS Attack
D) BIP attack
E) Parity Wallet Attack
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17
R3 Corda does not organize time into blocks. What does Corda actually perform and use? <strong>R3 Corda does not organize time into blocks. What does Corda actually perform and use?  </strong> A) Ripple is implemented as the blockchain and XRP for cryptocurrency. B) Notary services and timesmapping C) R3 Corda is a blockchain and does use blocks D) Notary services and timestamping

A) Ripple is implemented as the blockchain and XRP for cryptocurrency.
B) Notary services and timesmapping
C) R3 Corda is a blockchain and does use blocks
D) Notary services and timestamping
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18
What are two cryptocurrencies that you would expect to see mining equipment with ASICS? (Select two.)

A) Bitcoin
B) Ethereum
C) Neo
D) Litecoin
E) Monero
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19
The___________________ is the runtime environment for smart contracts in Ethereum?

A) Metamask
B) Ether
C) Mist
D) EVM
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20
Ethereum is considered to be a ______________type of blockchain.

A) Permissionless
B) Permission Based
C) Hybrid
D) Private
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21
Which of the following is NOT considered a token?

A) ICON
B) LTC
C) Golem
D) EOS
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22
______________is supposed to be the constant cost of network resources/utilization in the Ethereum blockchain? What is the constant?

A) Wei
B) Tether
C) Gas
D) Ether
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23
The Hyperledger Fabric business network is divided into three categories. What are the three categories? (Select three.)

A) Membership
B) Chaincode
C) Networking
D) EVM
E) Blockchain
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24
You are using Truffle for an Ethereum contract and would like to use a default set of contracts and tests from within an empty project directory. What is the syntax?

A) truffle defaults
B) truffle init
C) truffle test
D) truffle compile
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25
Every node needs to keep track of time AND it needs to be in synch with its other peer nodes on the blockchain. In Bitcoin for example the current median for time is around?

A) 7 minutes
B) 7 seconds
C) 17 seconds
D) 70 Minutes
E) 70 Seconds
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26
Ethereum has a metric system of denominations used as units of ether. What is the smallest denomination of Ether?

A) Kwei
B) Shannon
C) Wei
D) Finney
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27
Which of the following is NOT a requirement of an enterprise blockchain typically?

A) Append-only distributed system of record shared across business network
B) Cost efficient blockchain
C) Transactions are endorsed by relevant participants
D) Ensuring appropriate visibility; transactions are secure, authenticated & verifiable
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28
In Hyperledger Fabric, the smart contract logic is also called by two other names _______________ and ______________? (Select two.)

A) CordApps
B) DApps
C) Programmatic Logic
D) Ripple
E) Chaincode
F) Ledger
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29
Which of the following enterprise blockchains have a pluggable framework consensus algo? (Select two.)

A) Quorum
B) R3 Corda
C) Ethereum
D) Hyperledger Fabric
E) Ripple
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30
The block creation time is set to how many minutes in Bitcoin? 

A) 1
B) 10
C) 120
D) 100
E) 15
F) 150
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31
You have flown to NYC to have a discussion with a technical executive of a too big to fail bank. You are having a discussion about blockchain algos and the customer is asking what are some disadvantages of using a POW algo?

A) Centralization of blockchain control
B) Only use case for computational power is blockchain
C) Large expenditures for computational power
D) Not profitable for miners
E) 51% attack mitigation
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32
How many peers in the network need to endorse a transaction in a Hyperledger Fabric blockchain?

A) The number of peers required to endorse a transaction is driven by the IAM policy that is specified by the ledger.
B) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified by the DApps.
C) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified by the ledger.
D) The number of peers required to endorse a transaction is driven by the endorsement policy that is specified at chaincode deployment time.
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33
You are using Geth and you would like to list the accounts controlled by the node. What is the command?

A) geth list accounts
B) geth account node list
C) geth account node
D) geth account list
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34
Which of the following blockchain key components state how the transactions will be confirmed?

A) Distributed Ledger database
B) Validity Rules
C) Consensus Algorithm
D) Encryption
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35
What is diagram referencing below? <strong>What is diagram referencing below?  </strong> A) AND Gate B) XOR Gate C) OXR Gate D) NAND Gate

A) AND Gate
B) XOR Gate
C) OXR Gate
D) NAND Gate
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36
You are trying to generate a random number in Ethereum blockchain. What is the best way?

A) Wikipedia
B) Coindesk
C) Coinbase
D) Randao
E) ERC20
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37
What are two reasons that you would consider implementing a POW algo in your blockchain? (Select two.)

A) PoW imposes no limits on actions in the network and therefore can thwart attacks better than other algos due to high cost
B) What matters is to have large computational power to solve the puzzles and form new blocks over having a financial stake.
C) PoW imposes some limits on actions in the network and therefore can thwart attacks better than other algos due to high cost
D) The algo is energy efficient compared to POS and BFT
E) The algo is energy efficient compared to POS and DPOS
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38
When considering tokens on the Ethereum Blockchain what is the main difference between ERC20 and ERC721 tokens?

A) No difference on Ethereum all tokens are fungible
B) ERC20 is not fungible while ERC721 tokens are fungible
C) ERC721 is not fungible while ERC20 tokens are fungible
D) No difference on Ethernet all tokens are not fungible
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39
Gas has multiple associated terms with it: Gas Prices, Gas Cost, Gas Limit, and Gas Fees. The principle behind Gas is to have a stable value for how much a transaction or computation costs on the Ethereum network. Which is considered to be the static value for how much a computation costs in terms of Gas?

A) Price
B) Fee
C) Cost
D) Limit
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40
Is it possible to access the blockchain via an Ethereum Node?

A) Yes
B) No
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41
The CA (Fabric CA by default) issues a ______________ to each member (organization or individual) that is authorized to join the network.

A) rootCert
B) tCert
C) eCert
D) NodeCert
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42
In Ethereum a block contains two very important parameters. (Select two.)

A) Difficulty
B) Release date
C) Block number
D) Timestamp
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43
Select the best statement for determining how consensus is reached.

A) By the miner nodes which make sure that a transaction is valid.
B) By a cryptographic secure signature algorithm called ECDSA which makes sure that cheating is impossible.
C) By every single node in the blockchain network different transactions.
D) By every single node in the blockchain network executing the same transaction.
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44
What is provided by the Hyperledger Fabric to facilitate network communications?

A) API
B) SDK
C) Ruby
D) Middleware
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45
Composer Modeling Language is an object-oriented modeling language that defines the domain model for a business network definition. The modeling language is saved as a __________ file.

A) .json
B) .go
C) .txt
D) .ico
E) .cto
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46
When developing in Ethereum which is considered to be an In-Memory Blockchain simulations for rapid development?

A) Cpp-ethereum
B) Geth
C) TestRPC
D) Parity
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47
In regards to understanding the Ethereum Virtual Machine what statement is true?

A) The EVM is extremely powerful, non-turing complete and perfect for doing computational intensive thins, because of the direct access to the graphics card.
B) The EVM is extremely powerful, turing complete and perfect for doing computational intensive things, because of the direct access to the graphics card.
C) While the EVM is Sandboxed, it isn't as powerful as the Bitcoin network, because it's not Turing Complete
D) The EVM can't access hardware layers or anything outside a blockchain node because it's sandboxed.
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48
Fabric Ledger has two specific parts. Select answer with the proper two parts.

A) State Data, Transactional Data
B) State Data, Transaction logs
C) LevelIDb, CouchDB
D) Transaction Logs, CouchDB
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49
Ethereum currently uses the ___________Consensus Algo and in the future it is planned to go to the __________Consensus Algo?

A) PoW, DPoS
B) PoW, PoS
C) PoS, PoW
D) DPoS, PoW
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50
Hyperledger Composer has two main components. What are the two components? (Select two.)

A) Fabric
B) Sawtooth
C) Playground
D) Explorer
E) Business Network Archive
F) SDK
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51
Bitcoin implemented Byzantine Fault Tolerance through a system named:

A) Authenticated Encryption
B) Proof of Work
C) PBKDF2
D) None of the above
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52
What consensus algo uses a method of sending coins to an address where they cannot be retrieved?

A) Proof of Stake
B) Proof of Activity
C) Proof of Burn
D) Proof of Sending
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53
Chaincode Services uses Docker to host (deploy) the chaincode without relying on any virtual machine or computer language. What would be the main reason or best reason that Hyperledger chose containers over virtual machines?

A) Docker provides a secured, lightweight method to sandbox chaincode execution that is not "locked down".
B) Docker provides a secured, lightweight method to sandbox chaincode execution that is not "locked down" but additional programming languages cannot be enabled.
C) Docker provides a secured, lightweight method to sandbox chaincode execution that is "locked down".
D) Docker is fully compatible with Hyperledger and Linux with an upgrade subscription.
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54
The fabric framework is implemented on ______programming language. What programming language?

A) Go
B) Python
C) Node.js
D) Java
E) JS
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55
Hyperledger can best be described as a ____________________?

A) Blockchain that exclusively supports PoS Consensus
B) Permissionless blockchain
C) Token
D) Blockchain that exclusively supports PoW Consensus
E) Umbrella collaboration of open source blockchains
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56
What benefit does HPE Cloud Cruiser provide?

A) Need for proven, production-ready technology
B) Need a full history of all application data
C) Require top-notch performance
D) Need to avoid data duplication or redundancy
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57
Which is the right order for Ethereum Denominations?

A) Finney, Szabo, Mether, Wei
B) Gwei, Szabo, Finney, Ether
C) Finney, Szabo, Mether, Gwei
D) Wei, Finney, Szabo, Ether, Tether
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58
What is the difference in using Go-Ethereum over Ganache?

A) Can automate builds with Go Ethereum but you can't with Ganache
B) Go Ethereum is written in Java whereas Ganache is written in Golang
C) Go Ethereum is real blockchain whereas Ganache is a blockchain simulation
D) Ganache is a real blockchain whereas Go Ethereum is a blockchain simulation
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59
When you are developing with Fabric Composer which of the following is true?

A) Decreases the time of development
B) Simplifies the development of applications
C) Simplifies the integration of client applications
D) Increases the time of development
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60
In what year did a whitepaper that was published by "Satoshi Nakamoto" outlined a solution to the Byzantine Generals problem?

A) 2006
B) 2009
C) 2008
D) 2010
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61
How does a client app communicate with Hyperledger fabric chaincode (Smart Contracts)?

A) The app uses an SDK which invokes functionality on the chaincode which then announces the transaction to any peers required to endorse the transaction
B) The app uses Hyperledger Composer to communicate with CouchDB which in turn invokes chaincode functionality
C) Client apps don't communicate with Hyperledger fabric directly, they must use Hyperledger Composer for the transmission
D) The app points to a node's IP address, then calls an invoke function on the chaincode address to start the write process
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62
On the Ethereum blockchain the "nonce" of a transaction:

A) Holds the gas amount to be paid to the miner writing the block that contains the transaction
B) Is used to ensure that transactions by a given account are written in sequential order
C) Is reset to zero after each successfully mined blocked
D) Must always start with four zeroes
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63
Blockchain systems assume all parties are trusted by all other parties in the exchange or ecosystem.
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64
To interact with a deployed Ethereum Smart Contract, a user or app must:

A) Have a reference to the public address of the deployed Smart Contract
B) Have the appropriate permissions needed to invoke the functions of the Smart Contract
C) Have sufficient gas to perform read and write operations against the Smart Contract
D) All of the above
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65
Which of these is the name of a well known open source peer-to-peer hypermedia distributes file system?

A) FileBlocks
B) Hyperbole
C) FileDropper TM FileDropper TM
D) IPFS
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66
By design, permissioned blockchains such as Hyperledger Fabric are not capable of creating or utilizing cryptocurrency.
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67
What does the acronym DAO represent?

A) Distributed Autonomous Operations
B) Distributed Anonymous Organization
C) Distributed Anonymous Operations
D) Decentralized Autonomous Organization
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68
If a Proof of Work blockchain such a s Bitcoin or Ethereum changed to a Proof of Stake consensus paradigm, which key component of the Proof of Work process would be eliminated?

A) There would be no need for the miners or nodes to perform a guessing game
B) The need to solve Byzantine Fault Tolerance
C) All fees related to transactions would be removed
D) The blockchain network would no longer have to display public transactions
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69
Adding more nodes to a blockchain network has which effect?

A) Increased centralization
B) Increased security
C) Decreased costs
D) Increased performance
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70
Which of these reasons is a good reason to choose a conventional database over blockchain to store application data?

A) Centralization is to be avoided
B) Databases should never be used over blockchain
C) Full history is needed for all data
D) High performance is required
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71
One critical business consideration you must account for when choosing Hyperledger Fabric over Ethereum is:

A) Who you will have host the nodes and how will you deploy the network
B) If your blockchain will use Proof of Work or Proof of Stake
C) Which cryptographic algorithms Hyperledger Fabric employs
D) How you will implement your own gas/fee system
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72
Which of the following scenarios and databases is least suited to be utilized by a blockchain solution?

A) Scenario: Law enforcement system; Dataset: Criminal Arrests, Warrants for Arrest, Conviction Date
B) Scenario: An Email campaign service; Dataset: Recipient Email, From Email; Subject, Body
C) Scenario: A family filter wifi router; Dataset: Websites Visited, Websites Blocked, Download History
D) Scenario: Credit score app; Dataset: Credit Score, Hard Inquiries; Collections, Date Removed, Date Added
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73
Proof of Stake based blockchain systems use what design to permit valid write transactions?

A) A genesis "Stake" node approves or disapproves transactions announced from other nodes
B) Validator nodes each give or pay a stake in order to write transactions, and if malicious, will lose their stake
C) Stakeholders or early product investors host nodes that approve or disapprove transactions from other nodes
D) Every node on the network holds an equal stake, and if malicious, gets flagged for removal
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74
The word "Drapp" or "DApp" is most commonly understood to mean what?

A) Distributed Application
B) Distributed Apps and Programs
C) Decentralized Application
D) Distributed Autonomous Application
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75
Public blockchains can alter the blockchain ledger by:

A) Creating a hard fork of the blockchain data, tooling and/or software
B) Achieving community consensus via a Smart Contract to update the ledger
C) Re-hashing the blocks from the total block height down to the genesis block
D) Blockchain ledgers are immutable and can never be altered
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76
Which of these technical components best represents why cryptocurrency is able to operate successfully?

A) An immutable digital ledger that is validated and distributed across many peers
B) Using API calls, cryptocurrency having a direct correlation to USD exchange rates
C) High performance computing power allows cryptocurrency to be minted just as a central government might do with fiat currency
D) Blockchain cryptocurrency transactions are always public which generates user trust and adoption
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77
The first actual known blockchain software implementation and deployment occurred:

A) In 1991 by Stuart Haber
B) In 2011 Markus Persson
C) In 2009 by Satoshi Nakamoto
D) In 1991 by Linus Torvalds
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78
Which factor influences the gas cost to deploy a Smart Contact on the Ethereum blockchain?

A) None. Smart Contract deployment has a fixed gas cost
B) The types of operations written in code within the Smart Contract
C) The current Ethereum market conditions
D) The total size of the complied Smart Contract measured in kilobytes
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79
Blockchain systems can offer what advantage over centralized systems?

A) They are much easier to maintain and update
B) They have significantly higher transaction speeds
C) Their distributed ledger systems are more secure and immutable
D) All of the above
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80
Some of the various consensus models employed by public blockchain networks include:

A) Proof of Work
B) Proof of Importance
C) Proof of Stake
D) All of the above
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