A piston-cylinder assembly contains air, initially at 3.1 bar, 144 K, and a volume of 3.8 m. The air undergoes a process to a state where the pressure is 0.8 bar, during which the pressure-volume relationship is pV = constant. Assuming ideal gas behavior for the air, determine the mass in kg. Argon contained in a closed, rigid tank, initially at 50.7C, 3.8 bar, and a volume of 4.4 m, is heated to a final pressure of 7.5 bar. Assuming the ideal gas model with k = 1.57 for the argon, determine the heat transfer, in kJ.