During the isothermal heat addition process of a carnot cycle, 900 kj of heat is added to the working fluid from a source at 400°c. determine (a) the entropy change of the working fluid, (b) the entropy change of the source, and (c) the total entropy change for the process

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?