Levers can be found all around you. You can probably see one from where you are sitting right now! (Door, window opener, scissors) A lever is a simple machine that is used inside many other machines. Find out all about this simple machine in this title.Levers can be found all around you. You can probably see one from where you are sitting right now! (Door, window opener, scissors) A lever is a simple machine that is used inside many other machines. Find out all about this simple machine in this title.
4家庭擁有
0條書評(píng)筆記
