A trapezoidal channel has a bottom width of 5 feet, a slideslope (horizontal:vertical) of 2, and a depth of flow of 4 feet. The elevation of the channel bottom drops 2 feet every 1000 feet of horizontal distance traveled. The discharge in the channel is 382 ft3/s.
(a) Find the Manning’s roughness (n) required to create this flow condition.
(b) Determine the specific energy for this flow condition.