Alarge fraction of the thermal energy generated in the engine of a car is rejected to the air by the radiator through the circulating water. should the radiator be analyzed as a closed system or an open system?

Water vapor initially at 10 bar and 400 °c is contained within a piston-cylinder assembly. the water lost heat to the surrounding according to isochoric (iso-volumetric) process until its temperature is 150 °c. the water is then condensed isothermally to saturated liquid. for the water as a system, calculate the work in kj/kg