A trapezoidal channel has a bed width of $2\mathrm{.}0$ m and side slopes of $1\mathrm{.}5$ horizontal$=1$

vertical. The channel has a longitudinal slope of $1/9900.$ If the manning$$s coefficient of the channel

boundary of $0\mathrm{.}019,$ calculate the mean velocity and discharge in the channel boundary is $0\mathrm{.}018,$

calculate the mean velocity and discharge in the channel for a depth of $1\mathrm{.}9$ m$.$ Find the following

a$.$ Wetted Perimeter

b$.$ Hydraulic radius

c$.$ Mean Velocity by Manning$$s formula

d$.$ Discharge