A solid drug pellet with a top$-$surface susceptible to oxidation is covered with double layers of polyethylene $1\mathrm{.}0mm$ thick andnylon $0\mathrm{.}8mm$ thick to prevent oxygen contact and kept in a container of $30C.$Assume the oxygen pressure in the container is $0\mathrm{.}7$atm and that inside the drug is $0\mathrm{.}1$atm. Estimate the oxygen amount $($in mole$)$ that would penetrate into the top$-$surface area of drug with $1cm$ diameter after $1$ weeks storage. Permeability of oxygen to polyethylene is $4\mathrm{.}7*10^(-12)$ m$^2/$s$*$atm in $303$K$,$ and permeability of oxygen to Nylon is $0\mathrm{.}029*10^(-12)$ m$^2/$s$*$atm in $303$K$,$