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Home Q & A Board Science-Related Homework Help Geography and Earth Sciences
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dlrkd dlrkd
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9 years ago
A) The release of O2 from photosynthesis
B) Emissions from volcanic eruptions, primarily H2O, CO2, and NH3
C) Gases contained in meteorites, primarily N2 and H2
D) The composition of the solar nebula, which was rich in H2 + He
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bio_manbio_man
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9 years ago
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dlrkd Author
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#2
9 years ago
thanks~
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