Answer
$\dot{W}_s=2285\ kW$
Work Step by Step
From table A-6:
Outlet 2 ($P_3=50\ kPa, T_3=100°C$): $s_3=7.6953\ kJ/kg.K,\ h_3=2682.4\ kJ/kg$
Inlet ($P_1=3\ MPa, s_1=s_3$): $h_1=3851.2\ kJ/kg$
Outlet 1 ($P_2=0.5\ MPa, s_2=s_3$): $h_2=3206.5\ kJ/kg$
From the data given: $\dot{m}_1=2\ kg/s,\ \dot{m}_2=0.05\dot{m}_1,\ \dot{m}_3=0.95\dot{m}_1$
From the energy balance:
$\dot{m}_1h_1=\dot{m}_2h_2+\dot{m}_3h_3+\dot{W}_s$
$\dot{W}_s=\dot{m}_1(h_1-0.05h_2-0.95h_3)$
$\dot{W}_s=2285\ kW$
