Solved

The Proportion of Oxygen in Our Atmosphere Today

Question 16

Multiple Choice

The proportion of oxygen in our atmosphere today


A) has increased to 20% since before photosynthesis.
B) has remained about the same since the first organisms developed.
C) has decreased to 10%, from higher levels before photosynthesis.
D) increased rapidly since the development of water-splitting photosynthesis and eukaryotes.
E) has increased to 20%, including rapid increase since water-splitting photosynthesis and eukaryotes.

Correct Answer:

verifed

Verified

Unlock this answer now
Get Access to more Verified Answers free of charge

Related Questions

Unlock this Answer For Free Now!

View this answer and more for free by performing one of the following actions

qr-code

Scan the QR code to install the App and get 2 free unlocks

upload documents

Unlock quizzes for free by uploading documents