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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
Which one of the following statements is true for the Earth?
A)   The oxygen in our atmosphere was created by the evaporation of sea water and its dissociation into hydrogen and oxygen by solar UV light.
B)   The Earth has always had an oxygen-rich atmosphere, which was one reason that life could develop on the Earth.
C)   Out-gassing by volcanic eruptions converted the carbon-dioxide-rich atmosphere into an oxygen-rich atmosphere, thus creating conditions in which life could develop.
D)   Life developed in a carbon-dioxide-rich atmosphere and then converted it into an oxygen-rich atmosphere.
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
Very informative, I appreciate the extra effort
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