The correct answer should be B) Water vapor and carbon dioxide in the atmosphere trap heat.
The trapped heat cannot leave the atmosphere and as it is trapped, it increases the heat of the planet.
We are given
n = 87.3 moles He
no = 52.0 moles
Po = 9.63 atm
Using the relationship between Pressure and number of moles
Po/no = P/n
Substituting
9.63 atm / 52.0 mol = P / 87.3 mol
Solve for P<span />
Stronger intermolecular forces = higher boiling point
The stronger the intermolecular forces, the harder the molecules are to pull/break apart, which means a higher boiling point.