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Home Q & A Board Science-Related Homework Help Geography and Earth Sciences
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drelog drelog
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8 years ago
The Great Oxygen Event marks the time, approximately 2.5 billion years ago, when ________.
A) photosynthesis was clearly established and producing oxygen.
B) there was enough oxygen in the atmosphere to support a major burst of life on Earth
C) there was a cataclysmic weather event that absorbed most of the oxygen in the atmosphere and locked it into iron deposits in the oceans
D) there was a massive volcanic eruption that lead to a very rapid increase in oxygen levels on Earth
E) there was significant oxygen in the atmosphere
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Earth Science

Earth Science


Edition: 14th
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PulsaPulsa
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8 years ago
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drelog Author
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#2
8 years ago
Double checked your answer with my friend, it's right Smiling Face with Open Mouth
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