Multiple Choice
The atmosphere of early Earth is currently thought to have contained:
A) methane, water, ammonia, nitrogen, and oxygen.
B) carbon dioxide, water, oxygen, nitrogen, and hydrogen.
C) carbon dioxide, ozone, nitric oxide, water, and hydrogen sulfide.
D) carbon dioxide, water, carbon monoxide, hydrogen, and nitrogen.
E) carbon dioxide, carbon monoxide, water, hydrogen, and nitric oxide.
Correct Answer:

Verified
Correct Answer:
Verified
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