Paul was looking at the sample of Neon isotopes below. He calculated average atomic mass by doing the following: 20 + 21 + 22 = 63 / 3 = 21 amu
Paul is told that his answer is incorrect but doesn't know why. Explain what's wrong with his calculation & answer

An uncovered pot of water lies out in the sun. which statements correctly describe what happens at the surface of the liquid water? 1. the vapor pressure remains constant regardless of the water temperature. 2. the vapor pressure is produced by water molecules that have evaporated. 3. the vapor pressure increases as the sun heats the water in the pot. 4. evaporation stops once the vapor pressure reaches a certain point. 5. evaporation and condensation both occur on the liquid’s surface.