Refer to the figure below. Given: $L=4m$; for sand, $=17\mathrm{.}5k\frac{N}{m^3}$;${}^{\text{'}}=35$; and, for clay, ${}_{\text{s}\text{a}\text{t}}=19\mathrm{.}2k\frac{N}{m^3}$ and $c=45k\frac{N}{m^2}.$

Determine the theoretical value of $D.$

$($Enter your answer to three significant figures.$)$

$D=,m$

Determine the maximum moment.

$($Enter your answer to three significant figures.$)$

$M_{\text{m}\text{a}\text{x}}=,kN-\frac{m}{m}$