) [35 points] The enthalpies of formation of CO2,H2O,CH4, and C3H8 at TRef= 74,831kmolkJ,hfoC3H8=103,847kmolkJ,hfH2O=241,845kmolkJ. Considering complete ombustion in two separate constant pressure combustors with stoichiometrically correct nount of air (O2+3.76N2, to stable products write chemical balance equations for the two els: A=CH4 and B=C3H8 (d-1) write a conservation of energy equation for the processes of methane and propane combustion with stoichiometric amount of air (3.76 mols of N2 and 1mol of O2 ). Estimate the lower molar heating values LHVB and LHVA in kmolkJ of both fuels the basis of the heats of formation given above in kmolCO2kJ (d-2) find the CO2 emission index defined as: COO2A/B=(xA/xB)(LHVB/LHVA) of fuel B=C3H8 (propane) compared to fuel A=CH4 (methane), where xA and xB are numbers of carbon atoms per molecule of the fuels A and B