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某抗震蓬的顶部是圆锥形,这个圆锥的底面直径为10米,母线长为6米,为了防晒,需要...
某抗震蓬的顶部是圆锥形,这个圆锥的底面直径为10米,母线长为6米,为了防晒,需要在它的顶部铺上油毡,所需油毡的面积至少是( )
A.30米2
B.60米2
C.30π米2
D.60π米2
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