3. ( 35pts) A drying tower has been proposed to remove the residual monomers from spherical polymer beads that are 4mm in diameter. Drying experiments show that to a good approximation, the concentration of monomer in the pellet decays exponentially with time according to the relationship cM=cMOexp(t/0.0356). Where cMo is the initial concentration of residual monomer. Determine the tower height required for the pellets to lose 99.5% of the residual monomer during free fall through a stagnant air column. The density of the pellet is 995kg/m3, and density of the drying air is 1.2kg/m3 and its viscosity is 1.5105Pas