A flat plate coated with a volatile organic compound (VOC) is exposed to a parallel flow of atmospheric air at 20C, with a free stream velocity (i.e., upstream uniform velocity) of 5m/s. The length of the flat plate in the direction of the flow is 0.5m. The saturation concentration of the VOC in air at these conditions is 1.85109mol/cm3, and its diffusivity in air under these conditions is 0.068cm2/s. The density of the VOC is 1.21g/cm3 and its molecular weight is 140.2g/mol. Assume the viscosity of the air under these conditions to be 0.155cm2/s. Determine (A) the mass transfer coefficient, km for this system, and (B) the time it would take for the average thickness of the VOC layer to decrease by 1mm under these conditions. (Hint: though the system deals with diffusion of a solute through a gas instead of a liquid, the solution is similar. Be sure to select the correct equation that models this system.) (Ans: km=0.4.64scm;t= 11. 63 days)