Explain why the breathing rate of the students increased after exercise. Include information about what happens at the level of body systems and at the cell.

8 pound

Explanation:

As per Newtons law F = ma

where F is the applied force, m is the mass of object and a is the acceleration.

now if we see the equation : a= F/m

hence the acceleration is inversely proportional to the mass of the body.

If one ball has mass of 8 pound and another of 13 pounds then ball with less mass that is 8 pound will have greater acceleration.