Ammonia in a piston-cylinder assembly undergoes two processes in series. initially, the the ammonia is saturated vapor at p1 = 100 lbf/in.2 . process 1 − 2 involves cooling at constant pressure until x2 = 75%. the second process, from state 2 to state 3, involves heating at a constant volume until x3 = 100%. kinetic and potential energy effects are negligible. for 1.2 lb of ammonia: a. determine the heat transfer and work for process 1-2, in btu. b. determine the heat transfer for process 2-3, in btu.