For a construction project, a long rectangular channel of width B$1=25$m carrying a flow at a

volumetric rate of Q$=250$m$^(3)//$s at a normal depth of y$\_($n$1)=4$m needs to be temporarily narrowed to

B$2=13$m$,$ using sheet piles, at a certain location. Assuming a smooth transition $($no energy loss$)$ at

the contraction and that the bottom slope is very gentle, calculate all possible water depth forming

upstream, at and downstream of the transition, and plot and name the GVF profiles forming in the

channel.