An elevator is on the 20th floor of a 40-floor building. At time t = 0, the elevator is at rest and the doors have just finished closing. A student on the elevator has a smartphone with an app that can measure vertical acceleration. The student takes data for the 10 seconds starting at time t = 0; the acceleration data is shown in the graph on the right. Let positive values represent upward acceleration.

(a) Qualitatively and quantitatively describe the motion of the elevator at the following times.
i. Time t = 5 seconds
ii. Time t = 10 seconds
(b) At time t = 10 seconds, is the elevator above, below, or at its initial position? Explain your reasoning.
(c) On the grids below, draw graphs representing the velocity v and height y of the elevator as functions of time during the 10-second interval. Assume that the initial height of the elevator is y = y0. Be sure that your graphs have proper shapes and slopes during the appropriate times.