Describe what would happen if, while wearing rollerskates, you pushed as hard as you could against a wall. why does this happen?

Newtons 3rd law of motion can explain this. for every action there is an equal or opposite re-action. so if you push yourself you will roll backward, with the force of gravity acting on you, making you stop gradually. 

It true it will they want do take care headache, belly pain

By placing 2 fingers at the sternum (the spot where the lower ribs meet) the put the heel of your other hand next to your fingers. hope this