Consider an externally heated air gas turbine implementing the thermodynamic cycle described in Section 7.5. Using a compressor isentropic efficiency 0.85, determine the conversion efficiency of the system as a function of the pressure ratio, keeping the turbine inlet temperature fixed. What pressure ratio must be reached before the system can be started? Specify the mass flow rate, the thermal power input and output of the system, the compressor and turbine power, and pressure ratio at
(a) The maximum efficiency operating point, and 

(b) The minimum flow rate for 225 kW.