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artcher [175]
4 years ago
13

Near Earth’s surface, ____ occupies about 78% and ____ about 21% of the total volume of dry air. a. hydrogen; oxygen b. nitrogen

; oxygen c. oxygen; hydrogen d. nitrogen; water vapor
Biology
1 answer:
Paraphin [41]4 years ago
6 0

Answer: b.  Nitrogen; Oxygen

Explanation:

The air is a mixture of gases in the following percentage;

Nitrogen; 78%

Oxygen : 21%

Carbon(IV)Oxide : 0.03%

Argon : 0.9%

Others ( minute traces of Neon, Helium, Methane e.t.c) : 0.17%

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