Water in the form of saturated vapour at 100C is contained in an insulated piston-cylinder device (State 1). The water is allowed to slowly expand until the pressure reaches 20 kPa (State 2). (a) Show the process on a T-s diagram, indicating clearly the two states relative to the saturation lines. (b) Determine the volume ratio V2/V1. (c) Determine 1W2 (i.e. work done by the system in going from State 1 to State 2, in kJ/kg).