Introduction: This lesson provides students with a review of simple machines and their tasks. It works best in combination with your lesson on simple machines, or as a review/additional activity.
Throughout history, humans have developed several simple machines to make work easier. The most notable of these are known as the "six simple machines": the wheel and axle, the lever, the inclined ...
当前正在显示可能无法访问的结果。
隐藏无法访问的结果