Refrigerant R134a flows steadily at a mass flow rate of 2 kg/s through a well-insulated nozzle with a circular cross-section. The refrigerant enters the nozzle at 500 kPa, 30 C, 25 m/s and exits at 100 kPa. a) Determine the largest possible outlet velocity and the corresponding outlet temperature. b) If the outlet velocity is 250 m/s, determine the outlet temperature, isentropic nozzle efficiency, rate of entropy production in the nozzle, and the inlet and outlet diameters. Neglect changes in potential energy.