Estimation of the Overall Mass Transfer Coefficient Using the two-film mass transfer theory, calculate the overall air-water mass transfer coefficient of MCF and BF a) in a laboratory tank for a wind speed of 0.5 m/s measured 10 cm above the water surface, and b) at the surface of a lake for a wind speed of 15 m/s measured 3 m above the water. Assume an ambient (air and water) temperature of 25C, a system specific factor () of 0.5 in water and 0.67 in air, and a unit surface area.