5 Fill in the Blank 6 points When the professor sits on the skateboard and opens the valve of the fire extinguisher, a large volume of gas is type your answer. from the extinguisher very quickly. The square of the gas leaving the extinguisher in one square propels the professor on the skateboard in the square direction. Think back to Newton's 2nd law. If the professor had less typeyouranswer his acceleration would be type your answer.