What was the Great Oxygenation Event?
Group of answer choices
when cyanobacteria began...
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Chemistry, 20.12.2020 14:00 KKHeffner02
What was the Great Oxygenation Event?
Group of answer choices
when cyanobacteria began producing large quantities of oxygen through the process photosynthesis
when oceans and land mass oxygen reservoirs became full and free oxygen began to build up in the atmosphere
when the percentage of oxygen in the atmosphere rose to 35% 300 million years ago
when fish and amphibians began to breath oxygen 85 million years ago
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