Where is my bag? I can't see.
A:It's under the bed.
B:They are under the bed.
C:She is under the bed.
已知两个不同的平面α、β和两条不重合的直线,m、n,有下列四个命题:
①若m∥n,m⊥α,则n⊥α
②若m⊥α,m⊥β,则α∥β;
③若m⊥α,m∥n,n⊂β,则α⊥β;
④若m∥α,α∩β=n,则m∥n,
其中不正确的命题的个数是( )