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sergiy2304 [10]
2 years ago
12

When did oxygen first appear on earth

Biology
2 answers:
NNADVOKAT [17]2 years ago
5 0

Answer: 2.4 billion to 2.2 billion years ago

Explanation: the newton law act

Nonamiya [84]2 years ago
5 0

Answer:

3.1 Billion years ago

Explanation:

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