Question

what is the approximate percentage by volume of oxygen present in earths atmosphere in the given diagram? (not drawn to scale) a) 10% b) 33% c) 21% d) 46%

Explanation:

Step1: Recall atmospheric composition

The Earth's atmosphere by volume is approximately 78% nitrogen, 21% oxygen, and the rest is other gases (like argon, carbon dioxide, etc.).

Step2: Match with options

Among the given options (10%, 33%, 21%, 46%), the percentage of oxygen by volume in Earth's atmosphere is approximately 21%.

Answer:

C) 21%