Air enters the evaporator section of a window air conditioner at 100 kpa and 278c with a volume flow rate of 6 m3 /min. the refrigerant-134a at 120 kpa with a quality of 0.3 enters the evaporator at a rate of 2 kg/min and leaves as saturated vapor at the same pressure. determine the exit temperature of the air and the rate of entropy generation for this process, assuming (a) the outer surfaces of the air conditioner are insulated and (b) heat is transferred to the evaporator of the air conditioner from the surrounding medium at 328c at a rate of 30 kj/min