Repeat Example 9-3 using HEC-RAS but use a 100-yr storm at this location. Recalculate Q for a 100-yr .storm using the same C, A, and 7c information provided in Example 9-2 . Evaluate the behavior of the 7 x 3 box culvert and then examine the behavior of a 6 x 3 box culvert at this location. Document the diflerences in culvert performance, including weir flow depths for comparative purposes. Determine the minimum span (width) of box culvert needed to prevent overtopping of the roadway if the box culvert rise (height) allowed is increased to 4 ft.