KendrahX561393 KendrahX561393

03-11-2022
Biology

contestada

About how long ago did oxygen begin to accumulate in earth's atmosphere?A. 2 billion yearsB. 0.2 millionC. 2 millionD. 20 million

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AllyiahA88631 AllyiahA88631

03-11-2022

Oxygen was accumulated in the earth's atmosphere thanks to the origin of photosyntetic organisms about 2.4 billion years ago, which emitted oxygen as a result of the process.

So correct option is A. 2 billion years.

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