Show me the steps to solve d$)$ During a flood, the water level in the channel in Figure Q$1($d$)$ exceeded the bank full level of $3\mathrm{.}0$ m $.$ The flood bank has a bottom width of $12$ m $,$ located to the left of the main channel and it is grassed with side slope of $1V$:$3H.$ The estimated Manning's coefficient, n for the flood bank is $0\mathrm{.}035.$ The main channel has a roughness coefficient, $n$ of $0\mathrm{.}015$ and bottom width of $10$ m $,$ with a levee on its right and left at a side slope of $1V$:$2H,$ both sides. Survey measurements indicate the upstream elevation of the channel is $36\mathrm{.}5$ m and the downstream elevation of the channel is $35\mathrm{.}5$ m $,$ with the distance of $1$ km between both points. Solve for the total discharge for the compound channel. $($CO$1-$PO$1-$C$3)$

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