But you don't know that there is an easy one for you down at number four 4 if you haven't bothered to look at number four.

但是你不知道,在数字4的时候会有一个简单的题目,如果你没有尝试去看数字。

麻省理工公开课 - 固态化学导论课程节选

So, it's very easy to calculate, however, the number of radial nodes, and this works not just for s orbitals, but also for p orbitals, or d orbitals, or whatever kind of work of orbitals you want to discuss.

径向节点，的数量，这不仅对s轨道适用，对p轨道，d轨道，或者任何你们想讨论的轨道，都是适用的,它就等于。

麻省理工公开课 - 化学原理课程节选