O 246C In a closed ideal Brayton cycle with regeneration nitrogen gas is compressed from 150 kPa and 20C to 650 kPa and then heated to 1250C before entering the turbine. The highest temperature that air can be heated in the regenerator is: 576C 653C 729C 814C 972C QUESTION 4 An ideal Ericsson cycle with helium as a working fluid operates between temperature limits of 27C and 727C and pressure limits of 100 kPa and 1000 kPa. Assuming that the specific heats are constant at room temperature, the net work produced by the cycle is: 1272 kJ/kg 3353 kJ/kg 4486 kJ/kg 5451 kJ/kg 6326 kJ/kg