In a diesel cycle the pressures at points on the expansion curve are 12.5 kgf / cm2 and 3 kgf/cm2 respectively when the piston has executed 40% and 90% of the expansion stroke. If the cut off ratio is 1.6 and the compression and expansion follow the law PV1.36 = c and PV1.3 = c. Determine the compression ratio and the work done per cycle per unit mass. The pressure at the end of the expansion stroke may be taken to be 1.5 kgf /cm2. The temperature of air during suction is 30°C and R = 29.0 kgf-m / kg° C.