Question

what is the amount of oxygen present in the air

Answer 1

23% ozygen is present in air

Answer 2

By volume, dry air contains 78.09% nitrogen, 20.95% oxygen,0.93% argon, 0.04% carbon dioxide, and small amounts of other gases. Air also contains a variable amount of water vapor, on average around 1% at sea level, and 0.4% over the entire atmosphere.

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