100kg of methane is compressed from 0.5MPa and 300k to 3.0 MPa and 500K in a closed chamber by a compressor. The compression process is assumed to be adiabatic, calculate the efficiency of this compressor. Specific heat capacity of methane under constant pressure is 35.58 kJ/kmol.K and ideal has constant is 8.314 kJ/kmol.K