There is a small long straight river with a length of 2 km. some stones are on the river bed and some aquatic is on the side of bank. Given that the cross-section of the river is a trapezoid and mh side slope m = cota = 1.5. The bottom width and the water h=0.8 m depth are shown in the right figure. The bed drop is 1.0 m. Manning's roughness coefficient n for the river is 0.04 s/m3. -3 m Determine the flow rate Q using the Manning's equation. (g is taken as 9.81 m/s?)