Given that the hot thermal reservoir temperature is 250 C and the cold thermal reservoir temperature is 20 C, determine if each of the following 3 proposed heat engines (with operating parameters as follows) violates the first or second laws of thermodynamics: a. QH = 6 kJ, Q = 4 kJ, W = 2 kJ b. QH=8 kJ, Q = 4 kJ, W = 4 kJ C. QH = 8 kJ, Q = 6 kJ, W = 1 kJ (Of course, a heat engine that violates either of the laws cannot be realized.) CPS set 5, Problem 2: A refrigerator needs to accomplish a 1 kW rate of cooling to maintain a cold space at 4 C. What is the minimum rate at which heat will have to be rejected to the ambient at 30 C?