Conservation of Energy

The Undergraduate (Part 1/3)

A footloose undergraduate weighing 70 kg wants to bobsled down the Louvre. He pays the French government several million dollars in collateral, then sits on a bobsled on the top on of the Louvre. Then, he pushes himself off with a speed of 5 m/s. What is his speed at the bottom of the Louvre? Assume the undergrad is 21 m above the ground and that $g$ = 9.8 m/s. Round to the nearest tenth. Express your answer in m/s.