Question

question 1
0.5 pts
the atmosphere is approximately 80% ______ gas.
○ ch₄
○ n₂
○ co₂
○ h₂o

Explanation:

Earth's atmosphere is composed mainly of nitrogen gas ($N_2$), which makes up approximately 78% (often rounded to 80% for general approximation) of the total atmospheric gases. The other options are incorrect: $CH_4$ (methane) is a trace gas, $CO_2$ (carbon dioxide) is about 0.04%, and $H_2O$ (water vapor) varies but is not a major component at 80%.

Answer:

N₂