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Inessa05 [86]
3 years ago
13

(HELP QUICK!!) Earth's atmosphere was primarily composed of _______ until the Proterozoic era

Biology
2 answers:
Anuta_ua [19.1K]3 years ago
6 0

Answer:

methane

Explanation:

Sedaia [141]3 years ago
4 0

Answer:

C. Methane is the answer

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