a = Q4. Problem 5-5 in Dean. It is desired to determine the rate of diffusion of unreacted monomer out of a newly synthesized sheet of polymer. The model to be employed assumes that the monomer is initially at uniform concentration and that at t O the sheet is immersed in a well-stirred container of solvent in which the concentration is always negligible. The problem formulation is identical to that in Example 5.10-2 except that O(1,t) = 0 for all t. (a) Use the FFT method to determine O(x,t). (b) Calculate the average monomer concentration remaining in the sheet, Ot). (c) Determine the outward flux of monomer at the surface, both in dimensionless and in dimensional form