NEET BIOLOGY

Detailed explanation-1: -While oxygen is necessary for most life on Earth, the majority of Earth’s atmosphere is not oxygen. Earth’s atmosphere is composed of about 78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, and 0.1 percent other gases.

Detailed explanation-2: -Nitrogen is about 78% and Oxygen is 21%.

Detailed explanation-3: -78% of the air in the atmosphere is nitrogen.

Detailed explanation-4: -In fact, the troposphere contains three-quarters of the mass of the entire atmosphere. The air here is 78% nitrogen and 21% oxygen. The last 1% is made of argon, water vapor, and carbon dioxide.