In a magnetic disk unit, an arm on which magnetic heads are mounted.
磁盘机中一种用于安装磁头的臂状部件。
Above the unit disk means I don't care about this infinite surface.
在单位圆上方意味着，我不关心无穷远处。
It is going to be this unit disk.
它将会是这个单位圆。
because it's a unit disk. And, the center of mass is the center of a disk.
因为它是一个单位圆盘，这部分的中心就是圆盘的中心。
Now, of course the smart choice would be to just take the flat unit disk.
当然了，最佳选择是用单位圆盘。
Order number of ways: to disk as a unit, not retail sale.
数量订购方式：以盘为单位，不得以零售出售。
This unit mainly at each brand notebook maintenance and hard disk important data recovery.
本单位主要擅长各品牌笔记本维修和硬盘重要数据恢复。
This unit mainly at each brand notebook maintenance and hard disk important data recovery.
本单位主要擅长各品牌笔记本维修和硬盘重要数据恢复。
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