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Home Q & A Board Science-Related Homework Help Geography and Earth Sciences
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Mroche Mroche
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6 years ago

The primary source for free oxygen introduced into the atmosphere during the Proterozoic was
  through photosynthesis. Indicate whether the statement is true or false.
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joanneannajoanneanna
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6 years ago
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Mroche Author
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6 years ago
Thanks
Harvinder
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Yesterday
You make an excellent tutor!
gage
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2 hours ago
This calls for a celebration Person Raising Both Hands in Celebration
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