A high-temperature reservoir at T = 500°F is to be used as the heat source for a steady-state heat engine, and a low-temperature reservoir at T = 75°F is to be used as the heat sink. The boiler takes in a liquid organic compound at P = 5 atm and T = 100°F and expels the organic compound as a vapor at P = 5 atm and T = 470°F. The condenser takes in the organic compound as a saturated vapor at T = 100°F and expels it as a saturated at T = 100°F. The mass flow rate of the organic compound throughout the process is 500 lb_m/min. Relevant data for the organic compound include:

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Boiling point at P = 5 atm is 300°F. AĤ- 500 BTU/lb at T = 100°F and AĤ, 450 BTU/lb at T="300°F. = Liquid phase Ĉ, = 1.2 BTU/lb. Vapor phase heat capacity at P = 5 bar is Ĉ, = 1.5 + 0.0037 with T expressed in Rankine and C, expressed in BTU/lb.°R. A. Find the efficiency of a Carnot heat engine oper- ating between 500°F and 75°F. B. Find the efficiency of a Carnot heat engine oper- ating between T = 470°F and T = 100°F. C. Find the rate at which the entropy of the universe is increased by the processes in the boiler and the condenser.