12. Water is being discharged from a reservoir under a sluice gate at a rate of 20 m3 /s into a horizontal rectangular channel, 2 m wide, made of unfinished concrete. At a point where the depth is 1m, a hydraulic jump is observed to occur. Determine the following: a) The velocity before the jump b) The depth after the jump c) The velocity after the jump, and d) The energy dissipated in the jump (4 marks). Use table for manning's n