Revenge mark me brainliset
A seesaw is an example of a first class lever The fulcrum, which is the part of the lever that does not move, is in the middle. The resistance, which is the weight (person) you are trying to lift is at one end. The effort, which is the force applied to the lever, is the person sitting on the other end.
The circulatory system because it carries out cellular respiration and transports nutrients around the body
Opiates
Offtopic=(if you want something tasty make lemon poppy seed muffins, like OMG so good)
