ccrunnersd
2020-10-26T04:18:21+00:00
一张物理意义上成立的桌子,它的稳定性如何?
[img]https://img.nga.178.com/attachments/mon_202010/27/-7Q5-kc9oZuT3cSg1-mp.jpg.medium.jpg[/img]
[img]https://img.nga.178.com/attachments/mon_202010/27/-7Q5-kc9oZuT3cSg1-mp.jpg.medium.jpg[/img]