Explanation:
Why (for what reasons) is it believed that oxygen was not present when life formed on Earth? The life forms were anaerobic, and did not make oxygen. There is a lack of oxidized iron in rocks that are a few billion years old. Eventually oxygen from the oceans moved into the atmosphere, and iron could be oxidized.
B white blood cells are found in the lymph
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Answer:</h2>
the measured abundances of elements, the observed expansion of space, and the discovery of the cosmic microwave background 'CMB'. The CMB refers to the uniform distribution of radiation that pervades the entire universe.
