Refrigerant-134a enters the coils of the evaporator of a refrigeration system as a saturated liquid–vapor mixture at a pressure of 140 kpa. the refrigerant absorbs 180 kj of heat from the cooled space, which is maintained at 2108c, and leaves as saturated vapor at the same pressure. determine (a) the entropy change of the refrigerant, (b) the entropy change of the cooled space, and (c) the total entropy change for this process