【单选题】A 230-m 3 rigid tank is filled with saturated liquid-vapor mixture of water at 120 ° C. If 25% of the mass is liquid and the 75% of the mass is vapor, the total mass in the tank is ( )
【简答题】3–16 A rigid tank contains water vapor at 250°C and an unknown pressure. When the tank is cooled to 150°C, the vapor starts condensing. Estimate the initial pressure in the tank.