explain why a seesaw is closest in arrangement to a first - class lever.

Answer:

A seesaw is a first - class lever because in a first - class lever, the fulcrum is located between the effort and the load. In a seesaw, the middle point where it is supported is the fulcrum. The people sitting on either end of the seesaw are the effort and the load. When one person pushes down (applies effort), the other person on the opposite end (the load) moves up. The position of the fulcrum between the two makes it a first - class lever.

Brief Explanations:

First - class lever has fulcrum between effort and load. Seesaw has middle support as fulcrum with people as effort and load.