1. The problem statement, all variables and given/known data A tank half-filled with 40°C water is to be evacuated. What is the minimum pressure that can be expected in the space above the water? 2. Relevant equations Vp water @ 40 degrees = 3.38 3. The attempt at a solution I would have just subtracted the vapor pressure from the atmospheric pressure, but no temperature is given in this problem. I don't know how to take into account the fact that it's a half-empty tank. Thanks!