Question 1

Decrement operator, ??, decreases the value of variable by what number?
A)1
B)2
C)3
D)4

Accepted Answer

The decrement operator decreases the value of a variable by 1.

Question 2

Which right shift operator preserves the sign of the value? A)<< B)>> C)<<= D)>>=

Accepted Answer

The right shift operator (>>) preserves the sign of the value. It shifts the bits of the number to the right and fills the leftmost bits with the sign bit (the leftmost bit) to preserve the sign of the original number.

Question 3

What is the output of relational operators?
A)integer
B)boolean
C)characters
D)double

Accepted Answer

Relational operators compare two values and return a boolean result, either True or False, based on whether the comparison is true.

Question 4

. Which of these is returned by "greater than", "less than" and "equal to" operators?
A)integers
B)floating - point numbers
C)boolean
D)none of the mentioned

Accepted Answer

The "greater than", "less than", and "equal to" operators return boolean values (True or False) based on the comparison between the operands.

Question 5

Which of these jump statements can skip processing the remainder of the code in its body for a particular iteration?
A)break
B)return
C)exit
D)continue

Accepted Answer

The "continue" statement skips the remainder of the code in its body for the current iteration and proceeds to the next iteration of the loop.

Question 6

Which of the following is not a decision making statement?
A)if
B)if-else
C)switch
D)do-while

Accepted Answer

The "do-while" statement is a loop control statement that executes a block of code at least once and then repeatedly executes the block, or not, depending on a given boolean condition at the end of the block. It is not used for decision-making but for iteration, unlike "if", "if-else", and "switch" statements which are used to execute code blocks based on certain conditions, making them decision-making statements.

Question 7

Which of the following is not a valid flow control statement?
A)exit()
B)break
C)continue
D)return

Accepted Answer

exit() is not a flow control statement in the context of controlling the flow of execution within loops or conditional statements. It is used to exit from the program entirely. Break, continue, and return are used to control the flow within loops and functions.

Question 8

What is the range of short data type in Java script ?
A)-128 to 127
B)-32768 to 32767
C)-2147483648 to 2147483647
D)none of the mentioned

Accepted Answer

The answer of What is the range of short data...

Question 9

What is the range of byte data type in Java script?
A)-128 to 127
B)-32768 to 32767
C)-2147483648 to 2147483647
D)none of the mentioned

Accepted Answer

The range of byte data type in Java script is -128 to 127.

Question 10

An expression involving byte, int, and literal numbers is promoted to which of these?
A)int
B)long
C)byte
D)float

Accepted Answer

In Java, when you have an expression involving byte, int, and literal numbers, the entire expression is promoted to int if it doesn't explicitly involve long, float, or double values. This is due to the rules of binary numeric promotion and unary numeric promotion, where smaller data types (like byte) are promoted to int when they are used in expressions with other integral types.

Question 11

What is the numerical range of a char data type in Java script?
A)-128 to 127
B)0 to 256
C)0 to 32767
D)0 to 65535

Accepted Answer

In JavaScript, a char is not a separate data type, but characters are represented as strings with a length of 1. Internally, characters (and strings) in JavaScript are encoded using UTF-16, which means each character is represented by a 16-bit number, allowing for a range of 0 to 65535.

Question 12

Which of these coding types is used for data type characters in Java script?
A)ascii
B)iso-latin-1
C)unicode
D)none of the mentioned

Accepted Answer

JavaScript uses Unicode for character encoding, which allows it to represent virtually any character from any language.

Question 13

Which one is a valid declaration of a Boolean?
A)boolean b1 = 1;
B)boolean b2 = 'false';
C)boolean b3 = false;
D)boolean b4 = 'true'

Accepted Answer

In Java, a boolean can only be set to true or false directly, not with numeric or string values. Option C correctly assigns a boolean value.

Question 14

Which of these operators is used to allocate memory to array variable in Java script?
A)malloc
B)alloc
C)new
D)new malloc

Accepted Answer

In JavaScript, the `new` operator is used to create instances of objects, including allocating memory for array variables. The other options are not valid JavaScript operators for memory allocation.

Question 15

Which of these is an incorrect array declaration?
A)intarr[] = new int[5]
B)int [] arr = new int[5]
C)intarr[] = new int[5].
D)intarr[] = int [5] new

Accepted Answer

The correct syntax for declaring an array in Java involves specifying the type of the array, followed by square brackets, and then using the "new" keyword with the type again and the size of the array in square brackets. Option D, "intarr[] = int [5] new.", does not follow this syntax and is therefore incorrect.

Question 16

Which of these is necessary to specify at time of array initialization?
A)row
B)column
C)both row and column
D)none of the mentioned

Accepted Answer

When initializing a two-dimensional array, only the row size is necessary to specify; the column size can be inferred from the initialization context if not explicitly provided.

Question 17

Which of the following can be operands of arithmetic operators?
A)numeric
B)boolean
C)characters
D)both numeric & characters

Accepted Answer

Arithmetic operators can operate on both numeric values and characters. Numeric values are directly operated upon, while characters are treated based on their ASCII values. Boolean values, however, are not operated on by arithmetic operators.

Question 18

Modulus operator, %, can be applied to which of these?
A)integers
B)floating - point numbers
C)both integers and floating - point numbers
D)none of the mentioned

Accepted Answer

The modulus operator, %, can be applied to both integers and floating-point numbers in many programming languages, allowing for the calculation of the remainder of division operations across these data types.

Question 19

Which operator is used to invert all the digits in a binary representation of a number? A)~ B)<<< C)>>> D)^

Accepted Answer

The ~ operator is used to invert all the digits in a binary representation of a number, flipping 0s to 1s and 1s to 0s.

Question 20

On applying Left shift operator, <<, on integer bits are lost one they are shifted past which position bit?
A)1
B)32
C)33
D)31

Accepted Answer

When applying the left shift operator on integer bits in most programming languages, bits shifted past the 31st position (considering a 0-based index for bit positions in a 32-bit integer) are lost, as the 32-bit integer range is from 0 to 31.

Quiz 4: Java Script Operators and Data Types

Decrement operator, ??, decreases the value of variable by what number?

Which right shift operator preserves the sign of the value?

What is the output of relational operators?

. Which of these is returned by "greater than", "less than" and "equal to" operators?

Which of these jump statements can skip processing the remainder of the code in its body for a particular iteration?

Which of the following is not a decision making statement?

Which of the following is not a valid flow control statement?

What is the range of short data type in Java script ?

What is the range of byte data type in Java script?

An expression involving byte, int, and literal numbers is promoted to which of these?

What is the numerical range of a char data type in Java script?

Which of these coding types is used for data type characters in Java script?

Which one is a valid declaration of a Boolean?

Which of these operators is used to allocate memory to array variable in Java script?

Which of these is an incorrect array declaration?

Which of these is necessary to specify at time of array initialization?

Which of the following can be operands of arithmetic operators?

Modulus operator, %, can be applied to which of these?

Which operator is used to invert all the digits in a binary representation of a number?

On applying Left shift operator, <<, on integer bits are lost one they are shifted past which position bit?