Situation: You have been asked to estimate the rate at which water evaporates from the surface of a small lake. The lake is roughly circular with a diameter of D=1000[m]. The temperature of the water surface is 12[C]. Wind is blowing over the lake with temperature 18[C] and a relative humidity of 45%. The wind velocity is not known; however, a conservative estimate of the wind velocity is 1[m/s], which perhaps is low enough to not significantly disturb the lake surface. Requirements: Please, estimate the rate at which water evaporates from the lake surface: (a) Expressed in [kg/s]. Ans.: 3.58[kg/s] (b) Expressed in [gal/day] of liquid water. Ans.: 82,000 [gal/day]