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Biology 15 Online
OpenStudy (anonymous):

What gas was present in earth's earliest atmosphere and used by cyanobacteria during photosynthesis? A. oxygen B. nitrogen C. methane D. carbon dioxide

OpenStudy (phebe):

D

OpenStudy (phebe):

im sure

OpenStudy (phebe):

medal plzz @LOLAri

OpenStudy (phebe):

thanx

OpenStudy (anonymous):

NP

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