题干

某中学为研究学生的身体素质与课外体育锻炼时间的关系,对该校200名学生的课外体育锻炼平均每天运动的时间(单位:分钟)进行调查,将收集的数据分成 [0,10),[10,20),[20,30),[30,40),[40,50),[50,60) 六组,并作出频率分布直方图(如图),将日均课外体育锻炼时间不低于40分钟的学生评价为“课外体育达标”.
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I'm David.When I was 13,my parents decided that I should go to England to improve my English.I had never been to other countries before,so I felt a little worried.My parents prepared everything for my journey.My plane was due(预期)to leave at 9:30 a.m.and arrive in two hours.I phoned the English family who I would stay with and they told me they would wait for me at the airport(机场).

Unluckily my plane to London was delayed (延误).I tried to phone the English family again but I couldn't speak to them because they had already left home for the airport.

When I arrived in London.it was already 1:30p.m.I went to get my luggage(行李)but I couldn't find it.I became very worried.Luckily, the airport staff(工作人员)was very helpful and efficient.I didn't wait long-they found it 10 minutes later.

My English family were still waiting for me! I was so happy! Then my new life in London began.My English family were quite kind.I learned a lot of English because I spent most of the day talking in English.I played computer games with the little boy in my English family.I also taught him how to play chess.Sometimes I told him stories I learned from my family.

I missed my family during my stay in London.but I also feIt sad when my stay there came to an end.My English family held a party for me.I enjoyed it very much.I’ll never forget that summer in London! It is one of the most wonderful experiences I've ever had.