Carbon dioxide because every other option requires an input.
The condensation of water vapor formed the early oceans. It is an important part of the water cycle. It is easy to eliminate the other answers in this question. It can't be meteorites, living organisms, or nitrogen.
OK so very difficult but I will try,
a. 25%
b.75%
c. 50%
d. Male cats have only one X chromosome in their DNA meaning that they should be unable to inherit different colours.
