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jolli1 [7]
3 years ago
8

Oxygen was into ally created in earths atmosphere by___.

Biology
2 answers:
Mariulka [41]3 years ago
7 0
Here something that might help 
<span>
Most scientists believe that for half of </span>Earth's<span> 4.6-billion-year history, the</span>atmosphere<span> contained almost no </span>oxygen<span>. Cyanobacteria or blue-green algae became the first microbes to produce </span>oxygen<span> by photosynthesis, perhaps as long ago as 3.5 billion years ago and certainly by 2.7 billion years ago.</span>
kompoz [17]3 years ago
4 0
Blue-green algae........
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