JUST PROBLEM $3$ PLEASE!! $($i left #$2$ for reference$)$

Problem $2$

The soil profile shown in Figure $1$ consists of $5$ meters of compacted sandy clay underlain

by $5$ m of medium dense sand. Below the sand is a layer of compressible silty clay that

is $20$ meters thick. As shown in Figure $1,$ the initial groundwater table is located at the

bottom of the first layer $($i$.$e$.,5$ meters below the ground surface$).$ Neglect capillary rise in

this problem.

Figure $1$: Soil profile associated with Problem $2.$

$($a$)$ Compute the effective stress at mid$-$depth of the compressible clay layer.

$($b$)$ Then, assuming that the medium dense sand remains saturated, again compute the

effective stress at mid$-$depth of the compressible clay layer when the groundwater table

drops $5$ meters to the top of the silty clay layer.

Problem $3$

If the value of the coefficient of lateral earth pressure at rest $(K_0)$ for the compressible

silty clay layer of Problem $2$ is $0\mathrm{.}68,$ what are the total and effective horizontal stresses at

mid$-$depth of the layer in parts $($a$)$ and $($b$)$ of Problem $2?$