Why does an athlete run before taking a high jump ?

In the following situations identify the agent exerting the force and the object on which it acts.State the effect of the force in each case. Squeezing a piece of lemon brtween the fingers to extract its juice. Taking out paste from a toothpaste tube. A load suspended from a spring while its other end is on a hook fixed to a wall. An athlete making a high jump to clear the bar at a certain height.