Air flows through a device in which heat and work is exchanged. there is a single inlet and outlet, and the flow at each boundary is steady and uniform. the inlet flow has the following properties: flowrate 50 kg/s, t 25 °c, and velocity 150 m/s. heat is added to the device at the rate of 42 mw, and the shaft work is -100 kw (assume the efficiency is 100 %). the exit velocity is 400 m/s calculate the specific stagnation enthalpy (j/kg or kj/kg) at the inlet, and use the 1st law to calculate the specific stagnation enthalpy at the exit. assume constant cp1.0 kj/kg -k. calculate the temperature of the air at the exit. was the assumption of constant cp a good one?