题干

如图,△ABC和△DBC是两个具有公共边的全等三角形,AB=AC=6cm,BC=4cm,将△DBC沿射线BC平移一定的距离得到△D1B1C1,连接AC1,BD1.如果四边形ABD1C1是矩形,那么平移的距离为____.

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14cm

同类题4

阅读理解

    How could we possibly think that keeping animals in cages in unnatural environments, mostly for entertainment purposes, is fair and respectful?

    Zoo officials say they are concerned about animals. However, most zoos remain “collections” of interesting “things” rather than protective habitats. Zoos teach people that it is acceptable to keep animals bored, lonely, and far from their natural homes.

    Zoos claim to educate people and save endangered species, but visitors leave zoos without having learned anything meaningful about the animals' natural behavior, intelligence, or beauty. Zoos keep animals in small spaces or cages, and most signs only mention the species' name, diet, and natural range. The animals' normal behavior is seldom noticed because zoos don't usually take care of the animals' natural needs.

    The animals are kept together in small spaces, with no privacy and little opportunity for mental and physical exercise. This results in unusually and self-destructive behavior called zoo-chosis(圈禁性精神病). A worldwide study of zoos found that zoochosis is common among animals kept in small spaces or cages. Another study showed that elephants spend 22 percent of their time making repeated head movements or biting cage bars, and bears spend 30 percent of their time walking back and forth, a sign of unhappiness and pain.

    Furthermore, most animals in zoos are not endangered. Captive breeding(圈养繁殖) of endangered big cats, Asian elephants, and other species has not resulted in their being sent back to the wild. Zoos talk a lot about their captive breeding programs because they do not want people to worry about a species dying out. In fact, baby animals also attract a lot of paying customers. Haven't we seen enough competitions to name baby animals?

    Actually, we will save endangered species only if we save their habitats and put an end to the reasons people kill them. Instead of supporting zoos, we should support groups that work to protect animals' natural habitats.

同类题5

阅读下面的文章,回答后面练习题

                                思考着黑猩猩的思考

    游北京动物园的猩猩馆,里面一只苍老雄壮的黑猩猩,给我留下了很深的印象,它沉重地坐在地上,沉重地思考着

    它仰着脸,对众多游客不屑一顾的样子,眼睛瞅着上面那是一对暗黑色的眼睛,很深邃,深邃得让人感觉到那里面有着广阔的空间,感觉到那里面仿佛容纳了几万万年的历史

据说,人和动物的区别,是人能够思维,而动物不能思维的符号是语言,人是会说话的,而动物不会说,因此人比动物要高级得多所以,会说话的人才把不会说话的动物关在笼子里供消遣和欣赏

    而我宁愿相信,动物是有思想的,就像眼下的这位,肯定是在思考着它有充分的时间去思考它思考什么呢?不得而知留恋大自然中风情万种的自由自在?安于笼子里无忧无虑的生活?还是探索它生命存在的意义?

    有一点可以肯定,它无法摆脱人类的征服再凶猛的动物,都是怕人的,因为人类的思考比它们的思考要高级得多在人类面前,它们只有惧怕和无奈

    这是因为人类掌握着科学,而动物不掌握比方,聪明的鲁班发明了锯子,从此大片大片的森林就噼里啪啦倾倒了人类把石头制成了利器,后来又发明了火药,这一切都给动物们带来了灭顶之灾渐渐失去生存环境的动物们,在人们的驱赶杀戮中,惶惶然而不可终日它们成了人们身上的衣服和脚下的鞋子,成了人们饭桌上的美餐

    动物之所以是动物,是因为到现在它们依然过着风餐露宿的生活,而人类进化的程度,达到了不可思议的水平据说有的宴席,圆桌的中央,箍着一颗活猴子的头颅,众目睽睽下,一把重锤高高地举起,啪!然后食客们便津津有味地品尝着鲜嫩的猴脑

由此说来,眼下这位黑猩猩应该算是幸运儿,它不但没有被杀戮,而且还过着饭来张口的生活

    眼下在地球上,动物们的自由领域是越来越小了,黑猩猩也不例外原始森林悄然消失了,沙漠惊人地吞噬着绿洲,据说南极洲上面大气层的中间,也都洞穿了一个偌大的窟窿自由的人开始不自由了,沙漠、洪灾和干旱等等,开始袭击人类的生活人和动物一样,也感到了生存的危机,渐渐地有了与动物同舟共济的意识原本要杀戮的动物,成了稀有珍奇,受到了保护像这位黑猩猩这种现状,也是一种保护的形式,只是这种保护剥夺了其自由不过,它还可以思考

  思考不仅仅是人类的特长笼子里的黑猩猩仍在思考着……我思考着黑猩猩的思考