<span>The right answer is the option B. Close to 99 percent. The atmosphere is a mixture of gases: nitrogen, oxygen, CO2, H2O, argon, among others. Nitrogen is about 78% and oxygen is about 21%, so they two together constitute about 99 percent of the Earth's atmosphere.</span>
C. the square root of the mass of the particles.
<h3>Further explanation </h3>
Graham's law: the rate of effusion of a gas is inversely proportional to the square root of its molar masses or
the effusion rates of two gases = the square root of the inverse of their molar masses:

or

From this equation shows that the greater the mass of the gas, the smaller the effusion rate of the gas and vice versa, the smaller the mass of the gas, the greater the effusion velocity.
So if both gases are at the same temperature and pressure, the above formula can apply
Answer: calcium oxide will react with carbon dioxide to form calcium carbonate. I don't know if that's what you were asking.
Explanation: