A trapezoidal channel shown below with a longitudinal slope of 0.0009 and has chan­nel ban...

A trapezoidal channel shown below with a longitudinal slope of 0.0009 and has chan­nel banks on a side slope of  H:1V with dense vegetation. The estimated Manning "n" value of the channel is shown below.

Compute the discharge rate in the channel based on three channel segments where

Also compute the discharge rate based on the whole channel using an estimated Man­ning "n" value of 0.040. Explain the difference in the two discharge rates.