Air initially at 290 K, 1 bar undergoes the following processes:
1-2: polytropic compression to 5 bar with n = 1.19.
2-3: isentropic expansion to 1 bar.
a) Sketch the processes on a T-s diagram,
b) Determine the temperature of state 2 and
c) Determine the net work of the two processes in kJ/kg. (Assume air is an ideal gas).