At time t = 0 an elevator starts moving upward from the ground at a constant speed vo. At a later time t = T = 4.12s a marble is "let go" through the floor. In other words, imagine a marble resting on the floor of the elevator and a trap door of sorts opening up from under the marble. See the image below. The marble then hits the ground at a still later time t = T = 9.69 s. Let the maximum height that the marble obtains in this process be hmax and note that the marble obtains its maximum speed right before it hits the ground. What percentage of this speed does the marble have when it is at a height of hmar/2 above the ground? ground Vo elevator marble trapdoor opening