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若用半径为9,圆心角为120°的扇形围成一个圆锥的侧面(接缝忽略不计),则这个圆...
若用半径为9,圆心角为120°的扇形围成一个圆锥的侧面(接缝忽略不计),则这个圆锥的底面半径是( )
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A.1.5
B.2
C.3
D.6
考点分析:
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