A refrigerator, with coils at 28 C operates with a coefficient performance of 4.0 and a power input of 0.8 kW. Heat is rejected from the surrounding air at 20 C. Determine
a) the rate heat is rejected(kW),
b) the lowest theoretical temp inside the refrigerator(assuming COPrev=COP),
c) maximum theoretical power that could be developed by a heat engine operating between the coils and the surrounding air (kW)