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数据-2003,-2004,-2005,-2006,-2007的方差为( ) A...
数据-2003,-2004,-2005,-2006,-2007的方差为( )
A.-2
B.2
C.-
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164653593120047/SYS201310221646535931200008_ST/0.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131022164653593120047/SYS201310221646535931200008_ST/1.png)
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