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在△ABC中,斜边AB=4,∠B=60°,将△ABC绕点B旋转60°,顶点C运动...
在△ABC中,斜边AB=4,∠B=60°,将△ABC绕点B旋转60°,顶点C运动的路线长是( )
A.
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B.
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C.π
D.
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