Question

What two gases make up 99% of the Earth's atmosphere? A. Nitrogen and water vapor B. Carbon dioxide and oxygen C. Carbon dioxide and nitrogen D. Nitrogen and oxygen

Answer 1

Of the gases listed, nitrogen, oxygen, water vapor, carbon dioxide, methane, nitrous oxide, and ozone are extremely important to the health of the Earth's biosphere. The table indicates that nitrogen and oxygen are the main components of the atmosphere by volume.

so the answer is D. Nitrogen and oxygen

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