A player throws a ball vertically upward with a speed of 20ms−1 from the level ground. Take g=9.8ms−2.
(i) Calculate the maximum height reached by the ball above the point of projection.
(ii) Determine the total time for which the ball remains in the air before returning to the same level.
(iii) Find the magnitude and direction of the velocity of the ball 1.5s after it is thrown.