* Please be explicit with the procedure and use the Cengel tables. Thanks :)!

2600 lbm/h of butane is burned by complete combustion in a boiler with 25% excess air. Initially, the air and butane are at 14.4 psia and 77F. The products of combustion are at 1600F. Consider air as a 21%O2/79%N2 mixture. Decide: a) The heat flux produced in the boiler ________ Btu/hr

Consider Cp dependent on temperature.