Most (though not all) of the people who climb Mt. Everest do so with the aid of oxygen masks and tanks. This is because the barometric pressure at the peak of Mt. Everest is about one third that at sea level. Estimate the number of moles of oxygen in one cubic meter of air, assuming air is an ideal gas that is 21 mol% oxygen:

A. P = 1 bar and T = 25°C

B. P = 0.35 bar and T = 210°C