$7-11.$ A compressible $12-$ft clay layer beneath a building is overlain by a stratum of sand and gravel and un$-$derlamn Dy Impermeadle dearock. Ine total expected primary consolidation settlement of the compressible clay layer due to the building load is $4\mathrm{.}60$ in$.$ The coef$-$nicient of consolidation $($c$.)1$s $9\mathrm{.}04$ X $1010./$ mini$1.$ How long will it take for $90\%$ of the expected total primary consolidation settlement to take place?$2.$ Compute the amount Of Drimary consondationsettlement that will occur in $1$ yr$\mathrm{.}3.$ How long will it take for primary consolidation settlement of $1$ in$.$ to take place?