Water is flowing in a rectangular concrete channel. Apply the Manning equation to calculate the discharge. The channel is unfinished concrete 8 ft wide and drops 3 ft over a run of 1000 ft; the depth of flow is 2.5 ft ; T = 60°F; and the flow is uniform. Choose the closest answer (cfs): 

(a) 114,

(b) 145, 

(c) 183, 

(d) 212, or 

(e) 565.