【单选题】对于平面 α 、 β 、 γ 和直线 a 、 b 、 m 、 n ,下列命题中真命题是( )
A.
若 a ⊥ m , a ⊥ n , m ⊂ α , n ⊂ α ,则 a ⊥ α
B.
若 α ∥ β , α ∩ γ = a , β ∩ γ = b ,则 a ∥ b
C.
若 a ∥ b ,, b ⊂ α ,则 a ∥ α
D.
若 a ⊂ β , b ⊂ β , a ∥ α , b ∥ α ,则 β ∥ α
【简答题】Please list the basic functions of WTO.( )
【单选题】若a,b是异面直线,且a∥平面α,则b与α的位置关系是( )
【单选题】给出下列关于互不相同的直线l、m、n和平面α、β、γ的三个命题: 1若l与m为异面直线,l⊂α,m⊂β,则α∥β; 2若α∥β,l⊂α,m⊂β,则l∥m; 3若α∩β=l,β∩γ=m,γ∩α=n,l∥γ,则m∥n. 其中真命题的个数为( )
【简答题】A. ensure B. security C. difficult D. virtual E. easy F. community With the increasing popularity of the Internet as a 1 marketplace, consum...
【单选题】已知 α , β 是平面, m 、 n 是直线,给出下列表述: 1 若 m ⊥ α , m ⊂ β ,则 α ⊥ β ; 2 若 m ⊂ α , n ⊂ α , m ∥ β , n ∥ β ,则 α ∥ β ; 3 如果 m ⊂ α , n ⊄ α , m , n 是异面直线,那么 n 与 α 相交; 4 若 α ∩ β = m , n ∥ m ,且 n ⊄ α , n ⊄ β ,则 n ∥ α ...
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【简答题】All best__________ learned will be available on the online stadia__________ system. It will be __________ regularly, by contributors, in sports legislation, physical security, and cyber security and ...
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