题干

小兰在观察提琴,吉他,二胡等弦乐器的弦振动时突然想到这样一个问题:弦乐器的音调与那些因素有关呢?她认为:即使在弦张紧程度相同的条件下,发声的音调高低还可能与弦的粗细,长度,以及弦的材料有关,于是她想通过实验来探究一下自己的猜想是否正确,下表是她在实验时选择的琴弦条件.

编号

琴弦的材料

琴弦的长度/cm

琴弦的横截面积mm2

A

钢

20

0.3

B

钢

20

0.7

C

尼龙丝

30

0.5

D

钢

40

0.5

E

尼龙丝

40

0.5

上一题 下一题 0.0难度 选择题 更新时间:2012-02-07 06:28:46

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同类题1

学写短小的新闻。

新闻素材:

    公安部交通管理局最新统计表明,10年来,我国机动车增长率在15%以上,沿海经济发达省份增长率超过30%,已有8个省份的机动车超过百万辆。

    随着驾驶员和车辆数量的快速增长,与之相关的问题也随之产生。比如,如何确定汽车的价格和销售方法,道路的建设和收费问题,还有汽车售后服务、加油站设置数量、停车场布局是否合理等,有关部门正按照国务院发布的《汽车工业产业政策》,从宏观上加强汽车、道路、相关产业和设施、有关政策法规的协调发展。

    公安部交通管理局最新统计发现,10年来,我国已有近3000万人领取了机动车驾驶执照。在怀揣“驾驶本”的3000万人中,非专业司机占很大比例。

    随着改革开放不断向纵深发展,人们的思想观念也发生了很大的变化。在广大农村,很多有经济头脑的农民不再固守田园,靠种地为生,买卡车跑运输已成为农民致富的一个重要途径。在我国的城市中,行业与行业之间、行业内部之间的竞争越来越激烈,人们的危机意识也逐渐在加强。为了在激烈的竞争中能够站稳脚跟,立于不败之地,学开车和学电脑、学外语一起成为人们想要掌握的现代技能。

    根据公安部交通管理局最近统计,全国驾驶执照发放总数为2986万份,这个数字超过在公安部交通管理部门注册的2585万辆机动车总量。按最近统计,在上述部门登记的汽车为939万辆,摩托车为1100万辆。

(记者从公安部交通管理局获取)

请运用你所学过的新闻知识,将以上新闻素材整理成一则题目为《3000万中国人拿到“驾驶本”》的消息成稿。

要求:250字左右。根据题目对新闻素材进行筛选;保证新闻基本要素完备准确;能尝试根据重要性递减的原则对材料进行排序。

同类题3

阅读理解

    Friends are important to children.Research shows that children who have no friends can suffer from difficulties later in life.Friendship provides children with more than just fun.In making friends,children learn how to get in touch with others and solve problems.Having friends even does good to children for they can help each other during class.

    If the parents are concerned about whether their children make many friends,what matters is that the child is comfortable and happy with his friends.Parents need to understand the steps children take in building friendships.First of all,be a friend to your child.Good friendships start at home.Children begin to develop the necessary ability to go out and meet others through getting along with their parents. Greet the child warmly and let him know you are glad to see him.Children learn a lot from how their parents stay with them and other people.

    Teach children how to solve conflicts(争端).Being able to work out conflicts is an important skill in getting along with others.If parents know the children have a conflict,let them work it out on their own.Only step in if it is really necessary,for example,an argument is getting physical.

    Give children chances to practice staying together.Have children play games that require cooperation. For example,races are fun and provide plenty of practice in teamwork.“In what ways didn't you work well together? What might you do differently next time?” For these ideas,see books such as Games Book by Telly Orlick and Team—Building by Alanna Jones.

    Encourage children to show thanks to others.The parents can encourage children to do this by setting the example for them.