Q$3)$ For the given cantilever retaining wall system, perform the following stability checks:

a$)$ Wide$-$beam shear checks of the bottom stem thickness.

b$)$ Overturning stability check.

c$)$ Sliding stability check.

d$)$ location of the resultant force at the base and its eccentricity from the base centroid.

${}_{\text{c}\text{o}\text{n}\text{c}\text{r}\text{e}\text{t}\text{e}}=24k\frac{N}{m^3},f^{\text{'}}{?}^{\text{'}}=21$MPa,$LF=1\mathrm{.}7$