A mass-loaded piston/cylinder containing air is at 45 lbf/in.², 60 F with a volume of 9 ft³, while at the stops V = 36 ft³. An air line, 75 lbf./in.², 1100 R is connected by a valve, as shown in Fig. P4.154. The valve is then opened until a final inside pressure of 60 lbf/in^.2 is reached, at which point T = 630 R. Find the air mass that enters, work done, and heat transfer.