In a rectangular channel $($b $=2\mathrm{.}5[$m$],$ i $=0\mathrm{.}001)$ of lean concrete $($n $=0\mathrm{.}017)$ flows a flow Q $=3[$m$3/$s$].$ In the channel there is an upstream gate, followed at some distance L by a step of height a $=0\mathrm{.}35[$m$].$ downstream of the step there are no other singularities and the slope remains constant. Assuming that the gate operates with a $=0\mathrm{.}4[$m$],$ it is requested to:

$($a$)$ Classify the slope.

$($b$)$ Determine where normal runoff can occur in the channel.

$($c$)$ Calculate the runoff heights at all sections of the channel.

$($d$)$ If there are any shoulder$($s$),$ determine whether they are choked or unchoked.

$($e$)$ Plot the runoff, specifying the types of runoff.

$($f$)$ Plot the energy line.