Use the diagram below to help me answer questions 8-11. 8. What is the gradient of the water surface (S), the cross-sectional area (A) of the channel, and the wetted perimeter (P)? 9. What is the hydrologic radius (R) of the channel? 10. Calculate the average flow velocity (ft/second) in the channel using the Manning's formula. (I chose 0.04 or 0.05). 11. What is the average discharge through the channel (in m^3/second)? The diagram below is a cross-section through a steep, glacially-carved river channel. The crosssection has an almost perfect half-circle shape. The channel has a very rocky bottom with large cobbles and boulders. The channel is very steep and the water surface drops 15ft over a distance of 1100ft in a straight part of the channel. 7. Determine an appropriate Manning's n value to use in open-channel calculations and explain your choice (choose a value from the range of n= 0.01 to 0.1 ). (10 points) 8. What is the gradient of the water surface (S), the cross-sectional area (A) of the channel, and the wetted perimeter (P)?(10 points) 9. What is the hydraulic radius (R) of the channel? (10 points) 10. Calculate the average flow velocity (ft/second) in the channel using Manning 's formula. (10 points) 11. What is the average discharge through the channel (in m3/s) ? (10 points).