9-86 Consider a simple Brayton cycle using air as the work- ing fluid; has a pressure ratio of 12; has a maximum cycle temperature of 600°C; and operates the compressor inlet at 100 kPa and 15°C. Which will have the greatest impact on the back-work ratio: a compressor isentropic efficiency of 80 percent or a turbine isentropic efficiency of 80 percent? Use constant specific heats at room temperature. Qin (2) U (3 Compressor Turbine 1 4 Lout W net