A thrill-seeking student jumps off a bridge from the height H = 80.0 m above the water level. The student is attached to the bridge by an elastic cord so that she reaches zero velocity just as she touches the water. After some up-and-down bouncing, the student eventually comes to rest h = 20.0 m above the water level. What is the maximum speed reached by the student during the fall? Neglect air resistance and use 10.0 m/s2 for the acceleration due to gravity.

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