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prohojiy [21]
3 years ago
6

What is the approximate percent of oxygen by volume present in Earth's lower atmosphere?

Biology
1 answer:
Svetlanka [38]3 years ago
4 0

Answer:  21 percent

Explanation:

According to NASA, the gases in Earth's atmosphere include: Nitrogen — 78 percent. Oxygen — 21 percent. Argon — 0.93 percent.

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