A small spherical bead is used as a controlled drug-release capsule in the gastrointestinal system. In this particular case, a bead with radius R has a uniform initial concentration of cA0 of the drug griseofulvin (species A ). The diffusivity of griseofulvin within the bead material is DAB. Upon release from the bead, the drug is immediately consumed so that the surface concentration is essentially zero. (a) Write the general conservation equation and the initial and boundary conditions for the species A. (b) Transform the conservation equation and the initial and boundary conditions for the species A by using a substitution Q=rcA. (c) Solve the above and get the final expression using the general solution given below: ty=kx22y with y=C1atx=0,t0y=C2atx=l,t0y=f(x)att=0,0