The rigid tank illustrated in the figure has a volume of 0.06 m3 and initially contains a two-phase liquid-vapor mixture of H2O at a pressure of 15 bar and a quality of 0.2. The tank contents are heated. Heating continues until the final quality is x = 0.5. During heating, a pressure-regulating valve keeps the pressure constant in the tank by allowing saturated vapor to escape. Neglecting the kinetic and potential energy effects. (a). Determine the total mass in the tank at the initial and final states, in kg. (b). Calculate the amount of heat transfer, in kJ, from the initial state to the final state.