Air enters an insulated compressor operating at steady state at 1.05 bar, 23 degrees C with a mass flow rate of 1.8 kg/s and exits at 2.9 bar. Determine the minimum theoretical power input required, in kW, and the corresponding exit temperature, in degrees C. If the exit temperature is 147 degrees C, determine the power input, in kW, and the isentropic compressor efficiency. In addition, show the principal states and processes on a T-S diagram.