Air enters the diffuser of a turbojet engine with a mass flow rate (m) of 65 kg/s

Question:

Air enters the diffuser of a turbojet engine with a mass flow rate (m‹…) of 65 kg/s at 80 kPa, -40oC and a velocity of 245 m/s. The pressure ratio for the compressor is 10, and its isentropic efficiency is 87%. Air enters the turbine at 1000oC with the same pressure as the exit of the compressor. Air exits the nozzle at 80kPa. The turbine has an isentropic efficiency of 90%. Determine
(a) The rate of heat addition (Q‹…),
(b) The compressor power input (W‹… in) and
(c) The velocity of the air leaving the nozzle. Use the IG model.