A perfect gas has a molar mass of 26 kg/kmol and a value of y=1.26, calculate the heat rejected.-When unit mass of the gas is contained in a rigid vessel at 3 bar and 315C and then is cooled until...

A perfect gas has a molar mass of 26 kg/kmol and a value of y=1.26, calculate the heat rejected. -When unit mass of the gas is contained in a rigid vessel at 3 bar and 315C and then is cooled until the pressure falls into 1.5 bar. -When unit mass flow rate of the gas enters a pipeline at 280C and flows steadily to the end of the pipe where the temperature is 20C. Neglect changes in velocity.