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Which process do scientists think provided Earth with an oxygen-rich atmosphere?

photosynthesis


respiration


radiometric dating


spontaneous generation

User BigJump
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1 Answer

5 votes

Answer:

Photosynthesis

Step-by-step explanation:

Tiny organisms known as cyanobacteria, or blue-green algae conducted photosynthesis using sunshine, water and carbon dioxide to produce carbohydrates and oxygen.

User Basteln
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