题干

崇左市江州区太平镇壶城社区调查居民双休日的学习状况,采取了下列调查方式;a:从崇左高中、太平镇中、太平小学三所学校中选取200名教师;b:从不同住宅楼(即江湾花园与万鹏住宅楼)中随机选取200名居民;c:选取所管辖区内学校的200名在校学生.并将最合理的调查方式得到的数据制成扇形统计图和部分数据的频数分布直方图.以下结论:①上述调查方式最合理的是b;②在这次调查的200名教师中,在家学习的有60人;③估计该社区2000名居民中双休日学习时间不少于4小时的人数是1180人;④小明的叔叔住在该社区,那么双休日他去叔叔家时,正好叔叔不学习的概率是0.1.其中正确的结论是(  )

   

A:①④

B:②④

C:①③④

D:①②③④

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A

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    One day when I was 13, my family was working in the fields to clear away old brush when somehow the electric fence sparked(冒火星) and1a fire. We didn't see the fire2it had blocked the way to the only gate. I3to jump over the fence to safety but the fire was all around us. I could only watch in4as the flames continued to rise. Little did I know that my father had once been a(an)5and knew what to do.6with only a pump sprayer, buckets, and his boots, he7down to the nearby pond, filled the buckets and the sprayer, and began spraying the8while my older brother threw water with the buckets. Soon the wind9 however, and with the Fire Department too far away to arrive in time, my father began to stomp(踩灭) out the flames as he moved to the10 so that my family was able to move inch by inch toward the gate.11he arrived at the gate, he jumped into the truck, rolled up the windows, and drove12the fire. Then the fire was put out, and my mother was looking at my father with her13eyes.

    After that, my father began telling us about his days as a firelighter, and my brother and I became14 asking him what other jobs he had done before he15 Well, it turned out that he had done just about16except brain surgery!

    He had been in the military as a carpenter, carpet layer, and electrician, and had built B2 bombers before being poisoned in an accident that had17him to retire. My father has a blood disorder as a result of that18 but that hasn't stopped him from being a full-time electrician.

    To all those people whose fathers have worked in the military and in other dangerous jobs, be19of them, and remember that some day their20might save your life.