Dry air is essentially a mixture of the following entities: ,N₂, O₂ , Ar, and CO₂. The composition of dry air, in mole percent, is 78.08% N₂, 20.95% O₂, 0.93% Ar, and 0.04% CO₂. 

(a) What is the mass, in grams, of a sample of air that contains exactly one mole of the entities? 

(b) Dry air also contains other entities in much smaller amounts. For example, the mole percent of krypton (Kr) is about 1.14 x 10^-4 %. Given that the density of dry air is about 1.2 g/L at room temperature, what mass of krypton could be obtained from exactly one cubic meter of dry air?