$(25$p$)$ Ignore the immediate settlement, and calculate consolidation settlement of soil profile composed of sand and clay layer due to $200$kPa net foundation loading. Take unit weight of water as $10k\frac{N}{m^3}$ and assume that Skempton Bjerrum Correction Factor ${}_s$ is $0\mathrm{.}74$ for clay layer. Note that ${}_c($or sometimes shown as ${}_p)$ is the pre$-$consolidation pressure.