One way to determine the speed of a current in a river is to measure the width of a bridge and then count the number of seconds it takes a leaf to pass under the bridge. Suppose you are on a bridge that is 42 feet wide and you count the number of seconds it takes to pass under the bridge and it is 9 seconds. What is the speed of the current in m/h? Round to the nearest hundredth. There are 5280 feet in one mile.