Steam at 6.0 MPa and 700 K enters a converging nozzle with a negligible velocity. The nozzle throat area is 8 cm2. Assuming isentropic flow, plot the exit pressure, the exit velocity, and the mass flow rate through the nozzle versus the back pressure Pb for 6.0 ≥ Pb c ≥ 3.0MPa. Treat the steam as an ideal gas with k =1.3, cp= 1.872 kJ/kg · K, and R =0.462 kJ/kg · K.