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如果一个扇形的半径是1,弧长是,那么此扇形的圆心角的大小为( ) A.30° B...
如果一个扇形的半径是1,弧长是
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101193857253480427/SYS201311011938572534804003_ST/0.png)
,那么此扇形的圆心角的大小为( )
A.30°
B.45°
C.60°
D.90°
考点分析:
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