研究人员随机调查统计了某地1000名“上班族”每天在工作之余使用手机上网的时间，并将其绘制为如图所示的频率分布直方图．若同一组数据用该区间的中点值作代表，则可估计该地“上班族”每天在工作之余使用手机上

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研究人员随机调查统计了某地1000名“上班族”每天在工作之余使用手机上网的时间，并将其绘制为如图所示的频率分布直方图．若同一组数据用该区间的中点值作代表，则可估计该地“上班族”每天在工作之余使用手机上网的平均时间是（）

A：1.78小时

B：2.24小时

C：3.56小时

D：4.32小时

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C

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When I was a little girl, I lived with my grandparents in a small village(村庄).The life there was 1, and I liked it very much. I had many friends and I liked playing with them 2 . After rainy days, there was much 3 in the river(河) near our house. I often went there to get4with my friends. I had 5fun living there.
Now I live in a big city. I study in a school, but I6my life here. It’s too busy and it often makes me very7. Now the most interesting thing for me is to go to my grandparents’ home to8my vacation. Every time I can’t 9to go there. I 10 a quiet life. I hope to live in a village when I’m older.

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