Which would best describes what occurs when a ball is thrown against a wall? a) the ball will not bounce off the wall. b) the ball hits the wall hard enough to bounce off of it. c) the wall is stronger than the ball and neither exerts any forces. d) the ball exerts a force on the wall and the wall exerts a force back.

D)The ball exerts a force on the wall and the wall exerts a force back.

Explanation:

Newton's third law of motion states that:

"When an object A exerts a force on another object B, then object B exerts an equal and opposite force on object A"

In this problem, we can identify (for instance) object A with tha ball and object B with the wall. Therefore, if we apply Newton's third law, we get:

The ball (object A) exerts a force on the wall (object B), therefore the wall (object B) exerts an equal and opposite force on the ball (object A). So, option D is the correct one.

more than, less

less than, more

the old price per ounce is c/4.

the new price per ounce is c/3.6.

the ratio of the old price to the new one is

(c/4)/(c/3.6) = (c/c)×(3.6/4) = 0.9 . . = 9/10 . . "nine tenths" in either form