A diesel engine has a compression ratio of 20 and a cutoff ratio of 2. Air is at 95 kPa and 290 K at the beginning of the compression process, with a volume of 0.5 L. The temperature reaches 1800 K at the end of the combustion process. Assuming variable specific heats,
a) Determine the maximum pressure, P2 (in Kpa)
b) Calculate the thermal efficiency.