Acombined cycle power plant has a net power output of 287 mw. air enters the compressor of the brayton cycle at 280 k and 100 kpa. the pressure ratio is 21, the turbine inlet temperature is 1600 k and the gases leaving the turbine are used to heat the steam of the rankine cycle to 500oc and 4 mpa. the combustion gas leaves the heat exchanger (hrsg) at 400 k and the condenser pressure is 10 kpa. the isentropic efficiency of the compressor is 90%, the gas turbine efficiency is 91%, the steam turbine efficiency is 94% and the pump efficiency is 68%. determine: a. heat input in the combustion chamber, qin (in kw) b. the overall efficiency of the cycle.