An air standard Brayton closed cycle receives air at 1 atm and 298 K. The upper temperature and pressure limits are 5 atm and 1100 K. a) Determine the cycle thermal efficiency for the internally reversible cycle. b) Determine the cycle thermal efficiency for the cycle when the compressor and turbine isentropic efficiency are 0.9. c) Compare the cycle efficiency with a Carnot engine operating between the same two limits.