The flight test data for a given airplane refer to a level-flight maximum-velocity run made at an altitude that simultaneously corresponded to a pressure altitude of 30,000ft and density altitude of 28,500ft. calculate the temperature (in °f) of the air at the altitude at which the airplane was flying for the test.

Air inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?