A glass filled with water has radius \(3 \mathrm{~cm}\); left open, in \(4 \mathrm{~h}\) the level has dropped \(1 \mathrm{~mm}\). Determine, in grams/hour, the rate at which water evaporates. Also determine how many water molecules evaporate in one second per \(\mathrm{cm}^{2}\) of surface area.