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Home Q & A Board Science-Related Homework Help Physics
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symbo symbo
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7 years ago
The large amount of free oxygen in the Earth's present atmosphere is primarily a result of
A)   out-gassing by volcanoes and other geological processes.
B)   biological processes such as photosynthesis.
C)   splitting of carbon dioxide into carbon and oxygen by solar ultraviolet light.
D)   carbon dioxide becoming dissolved in the oceans, releasing oxygen.
Textbook 
Discovering the Universe

Discovering the Universe


Edition: 7th
Authors:
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hyponoticahyponotica
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7 years ago
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symbo Author
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7 years ago
This helped my grade so much Perfect
logbi
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mmmm_dat_userna
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This calls for a celebration Person Raising Both Hands in Celebration
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