Problem $1(15$ pts$.$ total$)$

The field book data below depicts the existing ground at station $20+00.$

The roadbed design template is $30-ft.$ wide with $1\mathrm{.}5$:$1(H$:$V)$ slopes.

The subgrade elevation at this station should be $3250\mathrm{.}26$ ft $.$

$\backslash$table$[[3242\mathrm{.}19,3243\mathrm{.}39,3241\mathrm{.}59,3241\mathrm{.}69,3241\mathrm{.}19,3240\mathrm{.}69],[\frac{4\mathrm{.}8}{50},\frac{3\mathrm{.}6}{28},\frac{5\mathrm{.}4}{0},\frac{5\mathrm{.}3}{15},\frac{5\mathrm{.}8}{32},\frac{6\mathrm{.}3}{50}$