An air conditioner must maintain a computer laboratory at 18°C when the outside temperature is 30°C. The thermal load that must be removed from the room consists of heat transfers entering through the walls and roof of the laboratory at a rate of 75,000 kJ/h and from the computers, lighting, and occupants at a rate of 15,000 kJ/h. (a) Determine the maximum theoretical coefficient of performance and the corresponding minimum theoretical power required by the air conditioner, in kW (Ans: COPR, max = 24.25; W min = 1.03 kW;) (b) If the actual power required by the air conditioner for this duty is 8.3 kW, determine the coefficient of performance. (Ans: COPR = 3.01) (c) If the given temperature and thermal load are observed for a total of 100 hours and electricity costs are 13 cents per kW-h, determine the cost, in $, over that period for each of cases (a) and (b). (Ans: case (a), cost = $ 13.4; case (b), cost = $ 107.9)