3)
A turbine operates adiabatically with superheated steam entering at $T_1$ and $P_1$ with a mass flow rate $\dot{m}$. The exhaust pressure is $P_2$ and the turbine efficiency is $\eta$. For one of the following sets of operating conditions, determine the power output of the turbine and the enthalpy and entropy of the exhaust steam.
(a) $T_1 = 450^\circ C$, $P_1 = 8000$ kPa, $\dot{m} = 80$ kg/s, $P_2 = 30$ kPa, $\eta = 0.80$.
