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若l、m、n是互不相同的空间直线,α、β是不重合的平面,则下列命题中为真命题的是...
若l、m、n是互不相同的空间直线,α、β是不重合的平面,则下列命题中为真命题的是( )
A.若α∥β,l⊂α,n⊂β,则l∥n
B.若α⊥β,l⊂α,则l⊥β
C.若l⊥n,m⊥n,则l∥m
D.若l⊥α,l∥β,则α⊥β
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