The rate at which water is lost because of evaporation from the surface of a body of water may be determined by measuring the surface recession rate. Consider a slimmer day for which the temperature of both the water and the ambient air is 305 K and the relative humidity of the air is 40%. If the surface recession rate is known to be 0.1 mm/h, what is the rate at which mass is lost because of evaporation per unit surface area? What is the convection mass transfer coefficient?