A meter, for example, is not deduced from anything.

一米,打个比方,并不是推导得来的

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So, for example, it's not just the 2 p that we could actually take an electron from, we could also think about ejecting an electron from the 2 s orbital.

比如，我们不只可以从，2，p，轨道上,打出一个电子，还能考虑从，2，s，轨道上,发射出一个电子。

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