题干

 某中学对本校八年级学生及家庭成员中能卷舌和不能卷舌的遗传情况进行抽样调查,统计结果如下表:

组别

父母性状

被调查家庭数量

学生性状及数量

能卷舌

不能卷舌

第一组

能卷舌×能卷舌

150

124

26

第二组

能卷舌×不能卷舌

56

41

15

第三组

不能卷舌×不能卷舌

20

0

20

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同类题2

阅读下列短文,从每题所给的A、B、C和D项中选出最佳选项。

    When I was a child in Minnesota, the watermelon was too expensive for my family. One of my father's friends, Bernie, was a rich businessman. He had a large store in Saint Paul.

    Every summer, when the first watermelons arrived, Bernie would give us a call. My father and l would go to Bernie's place. We would sit on the dock (码头) happily and get ready for a big meal.

    Bernie would take out a big watermelon, cut it up, give us both a big piece and sit down next to us. Then we three would put our faces into the watermelon, eating it happily.

    In my father's eyes, Bernie was a real rich man. I always thought it was because he was such a successful businessman. Later I learnt that it was not Bernie's money that made my father think that. My father thought Bernie was rich because of the way he lived his life. Bernie knew when to stop working, get together with friends and enjoy his "watermelon".

    Some of us, no matter (不管) how much money we have, will never be free enough to eat our "watermelon". If you don't take the time to sit on the "dock" and enjoy life's small pleasures, your work is probably hurting your life.

    When I grew up, because l was too busy making money as a doctor, I forgot the lesson I once learnt on the dock. Well, now I've relearnt(重新学习) it. Although I'm still busy working as a doctor, I will try to slow down and take the time to enjoy the small pleasures of my life.