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如图,△ABC内接于⊙O,∠C=30°,AB=2,则⊙O的半径为( ) A. B...
如图,△ABC内接于⊙O,∠C=30°,AB=2,则⊙O的半径为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668867215/SYS201311031016366688672016_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668867215/SYS201311031016366688672016_ST/0.png)
B.2
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103101636668867215/SYS201311031016366688672016_ST/1.png)
D.4
考点分析:
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