Air enters an adiabatic turbine at 200 psia, 1100 F and 200 ft/sec and leaves the turbine at 20 psia, 480 F and 120 ft/sec. The mass flow rate through the compressor is 2700 lbm/min. Using approximate analysis (use the average of the inlet and exit temperatures to evaluate specific heats), calculate the a) Power output from the turbine b) Isentropic efficiency of the turbine