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如图是长和宽分别相等的两个矩形.给定下列三个命题: ①存在三棱柱,其正(主)视图...
如图是长和宽分别相等的两个矩形.给定下列三个命题:
①存在三棱柱,其正(主)视图、俯视图如下图;
②存在四棱柱,其正(主)视图、俯视图如下图;
③存在圆柱,其正(主)视图、俯视图如下图.
其中真命题的个数是 ( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182006_ST/images0.png)
A.3
B.2
C.1
D.0
考点分析:
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