Air at 500kpa, 980k enters a turbine operating at steady state and exits at 200kpa, 680k. heat transfer from turbine occurs at an average temperature of 320k at the rate of 40kj per kg of air ts are negligible. for air as an ideal gas with cp -1.05kj/kgk and r-0.287kj/kgk, determine a) the rate of power developed in kj per kg air flowing and b) the rate of entropy production within the turbine in kj/k per kg of air flowing