A rigid tank contains 8 kg of saturated vapor steam at 115 degrees c. The steam is cooled to the ambient temperature of 20 degrees c. (a) Sketch the process with respect to the saturation lines on a T-v diagram. (b) Determine the entropy change of the steam, in kj/kg. (c) For the steam and its surroundings, determine the total entropy change associated with this process, in kj/kg.