A bridge is placed in a long rectangular channel. The channel width upstream (u/s) and downstream (d/s) from the bridge is B = 3.5 m. The flow rate in the channel is 75 m/s, the channel bed slope is 1%, and the Manning roughness coefficient is n = 0.012. 1. What is the critical depth u/s from the bridge? 2. What is the u/s channel's normal depth? Is it subcritical or supercritical flow? 3. What is the minimum channel width such that the u/s WL is not influenced for this discharge?