Which of these surface temperatures would have the fastest rate of evaporation?

The rate of evaporation is influenced by the temperature difference between a surface and its environment, particularly in relation to the dew point temperature. When the surface temperature is significantly above the dew point, the air can hold more moisture, leading to a greater rate of evaporation.

In this case, a surface temperature that is 30 degrees above the dew point creates a substantial thermal difference, allowing for a rapid increase in the kinetic energy of the water molecules. This higher energy means that water can more easily transition from the liquid to the vapor phase, leading to faster evaporation. The greater the difference in temperature, the faster the molecules can escape into the air.

In contrast, if the surface temperature is at or below the dew point, the air is likely to become saturated with moisture, significantly slowing down the rate of evaporation. Therefore, the selection of 30 degrees above the dew point accurately reflects the conditions that would facilitate the fastest rate of evaporation.