$5\mathrm{.}1\mathrm{.}4$ Determine the uniform flow depth in a trapezoidal channel

with a bottom width of $8ft$ and side slopes of $1$ vertical to $2$

horizontal. The discharge is $120f\frac{t^3}{s}.$ Manning's roughness factor

is $0\mathrm{.}015$ and the channel bottom slope is $0\mathrm{.}004.$

$5\mathrm{.}1\mathrm{.}5$ For a trapezoidal channel and slope $S_0$ of $0\mathrm{.}0002$

with a $20ft$ bottom width and side slopes of $1$ vertical to

$1\mathrm{.}5$ horizontal$),$ determine the normal depth for a discharge of

$1100$ cfs$.$