You're walking on the sidewalk and witness your friends John and Mary walking in opposite directions collide. Both John and Mary are walking at approximately the same speed. John is bigger ( heavier, Wider, and taller) then Mary.

1. explain which one of Newton's three laws of mechanics you would use to find out the net force experienced by either John or Mary
2. explain how you might conclude whether John or Mary might have experienced more pain or damage during the Collision
3. how does the situation change if one of your friends was walking at twice the speed of the other?