A$90-$ft$-$wide creek flows under a bridge. The creek cross$-$section is approximately rectangular, with a Manning$$s n of $0\mathrm{.}025$ and upstream slope of $0\mathrm{.}0004.$ For a flow rate of $500$ cfs$,$ answer each of the following questions. $1.$ What is the normal depth in the upstream section if you assume a wide rectangular channel? $2.$ At the bridge section, the water depth is $3\mathrm{.}3$ ft$,$ which is greater than normal depth. Explain how this situation can occur. $3.$ As the flow encounters the bridge, the upstream flow is $3\mathrm{.}3$ ft deep with a momentum function of $516\mathrm{.}2$ ft$3,$ and the downstream flow is $2\mathrm{.}7$ ft deep with a momentum function of $360\mathrm{.}0$ ft$3.$ What is the force exerted by the flow on the bridge section? $4.$ For these conditions, what is the head loss in feet as the creek flows through the bridge section? Assume this is a short transition so that z$1=$ z$2$