Do Problem $14\mathrm{.}8$ in the text on page $629.$ Instead of using the ${20}^{\text{'}}$ dimensions provided, change the $20\text{'}$ to $13\text{'}$ to solve the problem.

$14\mathrm{.}8$ Determine the discharge through the following sections for a normal depth of $5ft$;$n=0\mathrm{.}013,$ and $S=0\mathrm{.}2\%.$

$13$

a$.$ A rectangular section $2\frac{O}{f}t$ wide.

b$.$ A circular section $0ft$ in diameter.

${13}^{\text{'}}$

c$.$ A right$-$angled triangular section.

${13}^{\text{'}}$

d$.$ A trapezoidal section with a bottom width of $20$ tt and side slope of $1($vertical$)$: $2($horizontal$).$

e$.$ A parabolic section having a top width of $20$ ft for a $5-ft$ depth.

$[$Hint: $A=\frac{2}{3}Ty,P_w=T+\frac{8}{3}(\frac{y^2}{T}),$ where $T$ is the top width and $y$ is the depth.$]$