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问题 单项选择题

（）成立于1863年，旨在不断爆发的武装冲突中，在绝对中立和公正的基础上，为平民、伤员和俘虏提供必要的人道主义帮助。

A.救世军

B.红十字国际委员会

C.澳大利亚志愿服务协会

D.美国联邦应急总署

答案

参考答案：B

填空题

Small dogs generally live longer than big dogs so that yappy Yorkshire terrier next door could be around for a long time. But body size isn’t the only factor that (36) how long dogs survive. Personality influences life span, too, according to a new study that might help explain how animal (37) evolve.
Research on animals from ants to apes has found that different (38) have different personalities. Some are timid, others (39) . Biologists have proposed that temperaments evolved along with life history. (40) , violent animals use a lot of energy fast in (41) short lives, the thinking goes, whereas calmer animals last longer, saving themselves to (42) later in life.
But it’s hard to run evolutionary (43) on these personalities in anything longer lived than a fruit fly. So evolutionary biologist Vincent Careau of Universit6 de Sherbrooke in Canada came up with an idea: dogs. "All these breed differences reflect an experiment on artificial selection," says Careau. (44) , but from generations of humans crossbreeding and selecting animals with traits---the ability to chase foxes into holes, or herd sheep, or sit attractively on a sofa.
But evolutionary physiologist Joseph Williams of Ohio State University in Columbus isn’t convinced that (45) . "For me, it still remains to be seen. Dogs are contrary to what you would expect in nature in terms of longevity," he says. Elephants live for decades, (46) . On the other hand, a Chihuahua will generally outlast a Saint Bernard.
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实验题

、下图探究光的反射规律中，第一步，改变          的方向，观察反射光线方向怎样改变；实验结论是：                                ；

第二步，把纸板的右半面F向前折或向后折，观察是否还能看到          。

实验结论是：                                             。
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