A natural gas consists of 85.0 mol% CH4 (methane), 14.0% C2H6 (ethane), 1.00% C3H8 (propane) a. What is the composition of the gas in terms of mass fractions? b. What is the composition of the gas in terms of volume fractions? c. How many m^3 will be occupied by 70.0kg of the gas at 8C and 550kPa? d. What is the density of the gas in kg/m^3 at STP? e. What is the specific gravity of this gas at 8C and 550kPa using air at STP as the reference?