Unless there are some tax effects, which might matter-- and taxes always complicate things--but disregarding tax effects, it doesn't matter which you do.

除非这里涉及到税负,可能会影响...,税款常常把问题变得复杂,但不考虑税的话,什么时候买是没区别的

耶鲁公开课 - 金融市场课程节选

But it's just too complicated and too -it's impossible to make it work perfectly.

但这非常困难,非常复杂,而且不可能尽善尽美

耶鲁公开课 - 金融市场课程节选

We're going to get to more complicated atoms eventually where we're going to have more than one electron in it, but when we're talking about a single electron atom, we know that the binding energy is equal to the negative of the Rydberg constant over n squared, so it's only depends on n.

我们以后会讲到，更加复杂的情况,那时候,不只有一个原子，但当我们讲，单个原子的时候，我们知道结合能，等于,负的Rydberg常数,除以n平方，所以它仅仅由n决定的。

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