A diver springs upward with an initial speed of 1.7 m/s from a 4.0-m board.
a) Find the velocity with which he strikes the water. [Hint: When the diver reaches the water, his displacement is y = -4.0 m (measured from the board), assuming that the downward direction is chosen as the negative direction.]
(b) What is the highest point he reaches above the water?