D. Biological activity
Explanation:
The earth's atmosphere became oxygen rich as a result of biological activities. Early earth atmosphere was toxic one and in its reducing state.
- The activities of micro-organisms such as cyanobacteria led to the production of oxygen.
- These organisms manufacture their food in the presence of sunlight and water in the process of photosynthesis.
- The bye product of this reaction is oxygen.
- The intense presence of these living organisms led to the surge in atmospheric oxygen.
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Photosynthesis brainly.com/question/4216541
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You can have error both human error i.e eye balling a measurement to what looks close. and then you have inherent error the error that is already in the equipment i.e a 2 scales one can give a measurement of x when set to zero and if put it on a second scale you could get a measurement of y when set to zero because of calibration gravity etc things you cant control
Answer:
produce proteins (A) .......
