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下面图形的面积____

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    Students perform better when their instructors use hand gestures—a simple teaching tool that could generate benefits in higher-level math such as algebra(代数).

    A study published in Child Development,the top-ranked educational psychology journal,provides some of the strongest evidence yet that gesturing may have a unique effect on learning.Teachers in the United States tend to use gestures less than teachers in other countries.

     "Gesturing can be a very beneficial tool that is completely free and easily employed in classrooms," said Kimberly Fenn,study co-author and assistant professor of psychology at Michigan State University."And I think it can have long-lasting effects."

    Fenn and Ryan Duffy of MSU and Susan Cook of the University of Iowa conducted an experiment with 184 second-,third- and fourth-graders in Michigan elementary classrooms.

    Half of the students were shown videos of an instructor teaching math problems using only speech.The others were shown videos of the instructor teaching the same problems using both speech and gestures.In the speech-only videos,the instructor simply explains the problem.In the other videos,the instructor uses two hand gestures while speaking,using different hands to refer to the two sides of the equation.Students who learned from the gesture videos performed better on a test given immediately afterward than those who learned from the speech-only video.

    Another test was given 24 hours later,and the gesture students actually showed improvement in their performance while the speech-only students did not.

    While previous research has shown the benefits of gestures in a one-on-one tutoring-style environment,the new study is the first to test the role of gestures in equivalence learning in a regular classroom.

    The study also is the first to show that gestures can help students transfer learning to new contexts—such as transferring the knowledge learned in an addition-based equation to a multiplication-based equation.

    Fenn noted that U.S.students lag behind those in many other Western countries in math and have a particularly hard time mastering equivalence problems in early grades."So if we can help them grasp this foundational knowledge earlier," she said,"it will help them as they learn algebra and higher levels of mathematics."

同类题4

阅读《寻找生命的意义》一文。回答小题。

       ①生命犹如红酒,犹如画卷,犹如一首歌,有痛苦也有升华。可生命的意义究竟是什么?它使我们匪夷所思!

       ②悲观者认为,生命犹如地平线,即使看得见,却摸也摸不到。他想,生命中有太多挫折,需要承受太多,压力太大,心,太累了,身体也累了。就如某地一名小学生,老师也是为了他好,仅仅骂了他一句,他却承受不住,去了那个也许美好的世界。可他却不知道,他的家人有多伤心!

       ③其实,我认为,生命是太阳,即使落下了,也能再次升起。虽然有些人很不幸,但仔细想想,他们能体会到常人所不能体会到的痛苦,而正是这些痛苦,才使他们成长。中国的校车也许出不了主席,但山沟里的孩子也许成得了总统,就如,林肯的父亲也只是个鞋匠。因此,这,也许是幸运的。

       ④北京男孩刘伟也以自己的行为诠释了生命的意义,“要么赶紧死,要么精彩的活着。”刘伟虽然失去了双臂,但他却没有因此放弃生的希望,他开始以另一种姿态生活,那就是用脚弹钢琴,他每天辛苦练习7个小时。终于,他在一年内获得了钢琴七级的水平。他可以独立了,可以养活自己了!它虽然很痛苦,但那也是痛并快乐着的!

       ⑤坎坷使我们成长,困难使我们成功。贝多芬即使耳聋也不放弃自己的梦想,经过多倍的努力,梦终飞。只有努力,才有成功;只有付出,才有回报。我们有什么理由放弃? 那就让我们共同努力,共同成长,共同放飞自己的理想吧!

       ⑥生命的意义是不放弃生的希望,是能为他人带来欢乐,是为社会做出贡献,不断提升自己的生命价值。

       ⑦不同的人生,有不同的色彩,有的绚丽,有的平凡,绚丽让我们品味绽放的热烈,平凡让我们品味落日的从容。只有实现人生的意义,才能让生命之花开的更加灿烂!

       ⑧让我们一起寻找生命的意义,在漫漫的人生路途中留下最美好,最辉煌的记忆!

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