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Alex Ar [27]
3 years ago
13

Free oxygen formed on earth after

Biology
1 answer:
harina [27]3 years ago
5 0

Answer: (1) photosynthesis occurred

Explanation: The photosynthesis process in cianobacteria changed the composition of earth's atmosphera, rising oxygen levels. This could be possible since photosynthesis used energy from the sun to produce energetic intermediaries to synthesize sugars, and as byproduct due to water photolisis, is oxygen.

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A de-shelled egg is placed in tap water. The egg grows in size.
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C I did your test and got 100% I’m a g at this I promise you
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In what two ways could a desert be found at 30°N?
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9. Do you think that the blue crab can survive out of water? Explain your answer.
Ira Lisetskai [31]

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blsea [12.9K]

Answer:

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i just did this test, 100% with these answers

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