The foundation size for the building below is $12m12m$ and the pressure under it is $200k\frac{N}{m^2}.$ Calculate the consolidation settlement of the clay layer long after construction. The soil properties are as follows: $[12$ points$]$

Clay: $e_0=0\mathrm{.}9$;$c_s=0\mathrm{.}04$;$c_c=0\mathrm{.}15$;OCR$=1\mathrm{.}0$;$y_{\text{s}\text{a}\text{t}}=20\mathrm{.}05k\frac{N}{m^3}$;${}_w=10k\frac{N}{m^3}$

Gravelly sand: ${}_{\text{s}\text{a}\text{t}}=20k\frac{N}{m^3}$;$y=17\mathrm{.}5k\frac{N}{m^3}$

Take $I=0\mathrm{.}175.$

At the end of a consolidation test for a specimen, the final settlement is reported as $5$ mm $.$ What is the settlement value at $t_{30\%}?[6$ points$]$