题目内容
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[主观题]
For two energy levels where E1 ＜e2, if n1 and n2 are the populations of electrons on e1 e2 respectively, population inversion means （＞ A、N1＞N2
B、N1 ＜n2＞
C、N1=N2
D、N2=0
提问人：网友jimohaoliang
发布时间：2022-01-07
题目内容
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