Three alternative processes shown in the accompanying figure are suggested to change the state of one kg of air from 0.8 MPa, 25°C (state-1) to 0.3 MPa, 60°C (state-5). Process 1-2-5 consists of a constant pressure expansion followed by a constant volume cooling, process 1-3-5 an isothermal expansion followed by a constant pressure expansion, and process 1-4-5 an isentropic expansion followed by a constant volume heating. Determine the work and heat transfer for each alternative.