In an insulated closed container, there is 1500 grams of saturated liquid vapor mixture water at 100 kPa pressure. Initially, 45% of the water mass is in the liquid phase. Then, all the water in the container is evaporated with the heater in the container. (a) Write the initial degree of dryness (b) Calculate the entropy change during the process? (Hint: The specific volumes in the initial state and the final state are equal. In the final state, the water in the container is saturated steam.)