Water is evaporating from a cylindrical container to stagnant air (this is a diffusion of A through a nondiffusing B or unimolecular diffusion). The initial distance between the water surface and the tube edge is 10cm. Calculate the time it will take for the level to go down 1cm. Assume that the cylinder diameter is 2cm and that the process is happening at room temperature and pressure. After you obtain the flux equation (which you have done before), do the mass balance and relate the change of elevation/volume with time