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如图,小明从半径为5cm的圆形纸片中剪下40%圆周一个扇形,然后利用剪下的扇形制...
如图,小明从半径为5cm的圆形纸片中剪下40%圆周一个扇形,然后利用剪下的扇形制作成一个圆锥形玩具纸帽(接缝处不重叠),那么这个圆锥的高为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689002_ST/images0.png)
A.3cm
B.4cm
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689002_ST/0.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689002_ST/1.png)
考点分析:
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