4. A boy stands at the top of a cliff of height, h, above the ground and throws a ball vertically upwards. The variation of time t and velocity v of the ball is shown in the figure below. 20 vertical projection velocity (m/s) -10 -20 -30 Figure 14 -40 Use graph above to determine; 10 1201 13.0 4.05.0 time (s) i. the time taken to reach the maximum height. (1 mark) aximum height to the ground below the cliff (1 mark)​