Methane gas is burned completely with 30% excess air at approximately atmospheric pressure. Both the methane and the air enter the furnace at 30(C saturated with water vapor, and the due gases leave the furnace at 1,500(C. The flue gases then pass through a heat exchanger from which they emerge at 50(C. Per mole of methane, how much heal is last from the furnace, and how much heat is transferred in the heat exchanger?