正确答案: ABC

真空不能传声是通过实验与推理的方法获得的 发出较强声音的喇叭能使它前面的烛焰“跳舞”，说明声波能传递能量 课堂上听到老师的讲话声,说明声音可以在空气中传播

题目：关于声现象下列说法正确的是 【 】

解析：ABC

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举一反三的答案和解析：

[单选题]Dearstudents,pleasereadeverysentencecarefully.___youare,____mistakesyou’llmake.

Themorecareful,thefewer

[单选题]下列各组句子中，加点词语意思相同的一组是( )(3分)

然后知生于忧患而死于安乐也 孙叔敖曰：不然。

[单选题]从汶川大地震到北京奥运会，再到残奥会等活动，“志愿者”一词在我们面前变成了一张张亲切的笑脸和一双双温暖的手，志愿者精神感动着我们每一个人。志愿者精神包括 （ ）①为他人开一朵花，为自己的生命增加一缕温馨

①②③④

[单选题]17．

short

[单选题]人口增长会带来维持人类生存与发展最基本条件的短缺，因此，必须控制人口增长。你认为控制人口增长关键是( )

少生

[单选题]Imagine you receive an e-mail that looks something like this: ARE YOU GOING TO CLASS TODAY? How does(61) this message make you feel? ( 62) did the sender use all capital letters? Was he or she angry，or did that person just (63) to turn off the Caps Lock (大写键) on the computer? This E-mail sounds like the (64) is shouting because using all capital letters in an e-mail is usually the way that people shout (65) ．Knowing when and where not to use capital letters is just one (66) 0f online manners．Don't do anything online that you wouldn’t do in (67) life Don't use information that (68)else has written，and (69) it，s yours． Do share your knowledge of the (70) with others．

reading

解析：61．D【解析】此处的message指上文的e-mail，而看邮件应为read an e-mail。

[单选题]下列产品的开发利用与环境保护无关的是（ ）

加碘食盐 B．无磷洗衣粉

[单选题]下列现象中不能说明分子在做无规则运动的是

空气中飘动的浮尘 D．在盛有热水的杯子中放几片茶叶，过一会整杯水都变成茶水