Which process provides most of the oxygen found
in earth's atmosphere?

The process responsible for producing most of the Earth's oxygen is known as photosynthesis

Explanation:

In this process, plants and certain other organisms convert sunlight into oxygen and other products.

c) 50% there are four chromosomes. after crossing over, 2 of the four have been changed. that means any gamete has a 2 in 4 chance or 50% chance of receiving the mutated chromosome.