catapult is highly an excellent example of a class 3 lever. those who say it is a first class lever must be having some sort of misconception. you see, the tension of the stretched string is the effort and the load is the object which is flung.
A catapult is a third class lever, as it has the effort between the load and the fulcrum. It uses the same principle as a fishing rod. Other examples of third class levers are the human arm, tongs, a shovel and a broom.
Actually, a catapult is both a class 1 and a class 3 lever. This is a class 3 lever when it is pulled back because the tension is in the middle which is the effort. The fulcrum is on one end and the load is on the other. When you let it swing, it is a class 1 lever because the fulcrum is not in the middle but still between the effort and the load. It is closer to the effort. I know you may be confused with all of the other incorrect answers you have gotten but I am one billion percent positive that this is the right answer.