An ideal gas cycle passes through the following mechanically reversible stages: 1 ) adiabatic compression, 2) isobaric expansion, 3) adiabatic expansion, and finally 4) process at constant volume Which of the following PV diagrams represents the process? (The cycle temperatures are T1=500K,T2=800K,T3=2000K and T4 =1000K ) a) Figure a) b) Figure b) c) Figure c) d) Figure d)