Helium gas flows through a well-insulated nozzle at steady state. The temperature and velocity at the inlet are 550oR and 50 fps, respectively. At the exit, the temperature is 400oR and the pressure is 400 psia. The area of the exit is 0.0085 ft2. Using the idealized nozzle assumptions, determine the mass flow rate in lbm/s through the nozzle.