Initially, an insulated rigid tank contains 2.01 kg of water at 277.7oC and 1 MPa. A heater in the wall of the tank maintains the wall temperature at 600oC. After a period of time, the pressure in the tank rises to 1.5 MPa. Determine the final temperature (oC) of the water in the tank. Assume variable specific heats (use the property tables for water).