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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 source of the life-supporting oxygen in our present atmosphere is thought to have been

(a)   biological processes of early life forms.
(b)   out-gassing from the interior of the early planet.
(c)   the capture of the gas from interplanetary space by the gravity of Earth.
Textbook 
Discovering the Universe

Discovering the Universe


Edition: 7th
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discovererdiscoverer
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symbo Author
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#2
6 years ago
Very informative, I appreciate the extra effort
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