1. The problem statement, all variables and given/known data: A ball is thrown vertically upward with a speed of 20.0m/s. i) How fast is it moving when it reaches 16m ii) How long is required to reach this height? iii) Explain why there are two answers. 2. The attempt at a solution I assume there are two vectors. The force of the ball going upwards and the force of gravity pulling the ball downwards. Thanks in advance for helping.