Methane (CH4) is burned completely with 80 percent excess air during a steady-flow combustion process. If both

Question:

Methane (CH4) is burned completely with 80 percent excess air during a steady-flow combustion process. If both the reactants and the products are maintained at 25oC and 1 atm and the water in the products exists in the liquid form, the heat transfer from the combustion chamber per unit mass of methane is
(a) 890MJ/kg
(b) 802MJ/kg
(c) 75MJ/kg
(d) 56MJ/kg
(e) 50MJ/kg