Air at a temperature of 15 oC passes through a heat exchanger at a velocity of 30 m/s, where its temperature is raised to 800 oC. It then enters a turbine with the same velocity of 30 m/s and expands until the temperature falls to 650 oC. On leaving the turbine, the air is taken at a velocity of 60 m/s to a nozzle where it expands until the temperature has fallen to 500 oC. If the air flow rate is 2 kg/s, calculate: (i) the rate of heat transfer to the air, (ii) (iii) the power output from the turbine assuming no heat loss, and the velocity at exit from nozzle, assuming no heat loss.