3. A hot air balloon is ascending steadily at a speed of 3 m s". A stone is released from the balloon and it reaches the ground after 3 s. (a) Find the velocity of the stone (i) when it is just released from the hot air balloon, and (2 marks) (ii) just before it reaches the ground. (2 marks) (b) Draw the velocity-time graph of the stone on a graph paper. (3 marks) (c) Find the height of the stone above the ground when it is released. (2 marks) (d) Explain whether each of the following statements is correct. (i) The acceleration of the stone is zero when it reaches its highest point. (2 marks) (ii) If a heavier stone is used instead, it would reach the ground in a shorter time. (2 marks) upwards velocity = 3 m s stone O Fig. 5.27