In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

Question: Scott rolls two balls together until they strike each other. When Scott rolls the balls softly, they barely move apart, and when Scott thrusts the balls at one another, they are apart a 
 Answer: great distance
When two skateboarders push against each other, it causes them to move apart. The harder they push together, the farther apart they move.