设 m,n 是两条不同的直线， α,β 是两个不同的平面，则下列命题正确的是①若 m⊥α,α⊥β ，则 m∥β ；②若 m⊥α,α∥β,n⊂β ，则 m⊥n ；③ m⊂α,n⊂β,m∥n ，则 α∥β

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设 m,n 是两条不同的直线， α,β 是两个不同的平面，则下列命题正确的是（）

①若 m⊥α,α⊥β ，则 m∥β ；

②若 m⊥α,α∥β,n⊂β ，则 m⊥n ；

③ m⊂α,n⊂β,m∥n ，则 α∥β ；

④若 n⊥α,n⊥β,m⊥β ，则 m⊥α .

A：①②

B：③④

C：①③

D：②④

上一题下一题 0.0难度选择题更新时间:2019-04-03 01:05:41

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D

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阅读下面短文，从短文后所给的A、B、C、D四个选项中选出能填入相应空白处的最佳选项。

Hi, everyone. I'm Daming. I come from a family 1 five people. They are my grandparents, my parents and me. We live in a tall building in Shanghai in the 2 of China. Our apartment is big and 3. We're living a happy life. My grandfather doesn't work now. He often tells me something about his 4.

My grandfather 5 born in 1958in a small village. At that time, there wasn't a 6 in the village. 7. My grandfather couldn't go to school. There was a 8 behind my grandfather's house. The water was clean and there were lots of fish in it. People in the village were friendly and they got on well with each other. People were busy on the farm all day. There were many interesting games for children to play. It was great for my grandfather to 9 other children, so he wasn't 10. My grandfather often says, “the life in the past was hard, but it was happy too.”

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