发表于2024-12-28
Seesaws NutcrackersBrooms Gateway Simple Machines 2024 pdf epub mobi 电子书
图书标签:
Explains the concepts of simple and complex machines and mechanical advantage, and describes levers, including crowbars, can openers, and wheelbarrows, and how they work.
Seesaws NutcrackersBrooms Gateway Simple Machines 2024 pdf epub mobi 电子书