Aclosed gas turbine unit uses helium as the working fluid. there are two stages of compression with intercooling from 480kpa and 290k to a maximum pressure of 2.75mpa with an intermediate pressure of 1149kpa. the regenerator has an effectiveness of 60% and delivers the helium to the high-temperature heat exchanger, where it is heated to 890k. there are two turbine stages, the first discharging at 1170kpa. following the first turbine stage, a heat exchanger re-heats the helium to 890k. the second turbine exhausts at 480kpa to the regenerator. all the expansion and compression processes are isentropic. a)- the compressor work per kilogram b)- the turbine work per kilogranm c)- the heat added to the cycle per kilogram d)- the thermal efficiency e)- the power output for a helium flow rate of 45kg/s