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Lesechka [4]
3 years ago
9

How is modern Earth different from Earth over four billion years ago?

Biology
2 answers:
Gelneren [198K]3 years ago
3 0

Answer:

D, over the past Billions of years, our atmosphere has formed to protect life.

Sergeeva-Olga [200]3 years ago
3 0

Answer:

B. Little to no oxygen

Explanation:

The atmosphere on the primitive Earth over four billion years ago was reducing. It did not have oxygen or oxygen was present in very little amount. The present-day atmosphere of today's Earth is rich in oxygen.  

Evolution of oxygen-evolving autotrophic cyanobacteria led to the accumulation of oxygen in the atmosphere of primitive Earth.  

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