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从8名女生,4名男生选出6名学生组成课外小组,如果按性别比例分层抽样,则不同的抽...
从8名女生,4名男生选出6名学生组成课外小组,如果按性别比例分层抽样,则不同的抽取方法种数( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124305644991589/SYS201310251243056449915008_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124305644991589/SYS201310251243056449915008_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124305644991589/SYS201310251243056449915008_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131025124305644991589/SYS201310251243056449915008_ST/3.png)
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