Consider a ball kicked horizontally off the edge of a building 20 m high with a speed of 20 m/s. Neglect any kind of friction. (i) What will the ball's speed be just as it is about to strike the ground below? Hint: Use conservation of total mechanical energy. (ii) If the ball were kicked off horizontally with twice as much speed but at the same height as before, how would the speed of the ball as it strikes the ground change? (iii) How would the time of fall change?