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A single acting compressor is required to deliver air at a pressure of 2.5 MPa from an induction pressure of 95 kPa, at the rate of 3.2 m³/min measured at free-air conditions of 100 kPa and 15 °C. The compression is carried out in two stages with ideal intermediate pressure and complete intercooling. The index of compression and expansion for both stages is 1.3. The speed of the compressor is 750 rpm. The temperature at the end of the induction stroke in the low pressure cylinder is 35 °C. If the clearance volume is 3% of the swept volume in each cylinder and the mechanical efficiency of the compressor is 90%, calculate: 4.1 The intermediate stage pressure 4.2 The indicated power required 4.3 The saving in indicated power over single-stage compression (3) 4.4 The swept volume of both cylinders (9) 4.5 The power output in kilowatts for the motor required (2) [20]