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如图,边长为1的菱形ABCD绕点A旋转,当B、C两点恰好落在扇形AEF的弧EF上...
如图,边长为1的菱形ABCD绕点A旋转,当B、C两点恰好落在扇形AEF的弧EF上时,弧BC的长度等于( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689004_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689004_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689004_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689004_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103102412276968998/SYS201311031024122769689004_ST/3.png)
考点分析:
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