9.
Unless specifically instructed to do so, what should you never put into a flame?

Gas

Explanation:

Do not put any sub- stance into the flame unless specifically instructed to do so. Never reach over an exposed flame. Light gas (or alcohol) burners only as instructed by the teacher.

< > according to newton's third law of motion, forces always act in equal but opposite pairs. another way of saying this is for every action, there is an equal but opposite reaction.< >