$7.$ A carbon steel test coupon installed in a crude pipeline of dimensions $2-$in$\backslash$times $3-$io$\backslash$times $0\mathrm{.}125$ in$.$ with a $0\mathrm{.}25-$in$.$ hole for suspending in ageressive water phase is exposed for $120$ bours $7\mathrm{.}78$g $/$ cm$^3.50$ millizrams. What is the corrosion rate in mpy for this pipeline? $($Density is $\mathrm{.}7\mathrm{.}78$g$^3$cm$^3,$ CR$=(534$W$)/$ D A T$)$