A novel heat engine operates a three-stage cycle using air as the working fluid in a closed system. The air is initially at 1 bar, 20C and is heated at constant volume to 660C. The air is then expanded adiabatically back to 1 bar, then cooled at constant pressure until it reaches the initial condition. Remember to clearly state any assumptions that you make. Sketch the cycle on a labelled P-V diagram. (i) (ii) (iii) Calculate the work done during the expansion process. Calculate the cycle efficiency.