Someone me for the second time for the following situations, describe the contact and non-contact forces that are involved.
1.a book sitting on a shelf
2.a soccer player kicking a ball; the ball soaring through the air and landing on the ground
3.a hiker in the woods reading her compass to determine which direction to go
4.a child on a sled; first, the child is sitting at the top of the hill, waiting his turn; then, the child pushes off and slides down the hill, eventually coming to a stop.