A natural gas mixture is burned in a furnace at a power-generating station at a rate of 13.0 mol per minute. (a) If the fuel consists of 9.3 mole CH4, 3.1 mole C2H6, 0.40 mol C3H8, and 0.20 mole C4H10, what mass of CO2 (g) is produced per minute? (b) How much heat is released per minute?