题干

对于实验室制备乙烯的实验,下列说法正确的是(  )

A:烧瓶中先加入反应药品,然后检查仪器的气密性

B:所用的反应药品为1体积酒精和3体积浓度为5mol/L的硫酸

C:收集乙烯可用排水法,也可用排空气法

D:温度计要插入反应液体的液面下,以控制温度在170℃

上一题 下一题 0.0难度 选择题 更新时间:2019-04-18 02:25:09

答案(点此获取答案解析)

D

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根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Evaluating (评价)Sources of health Information

Makinggood choices about your own health requires reasonable evaluation. A key firststep in bettering your evaluation ability is to look carefully at your sourcesof healthy information. Reasonable evaluation includes knowing where and how tofins relevant information, how to separate fact from opinions, how to recognizepoor reasoning, and how to analyze information and the reliability of sources.____ 

Goto the original source. Media reports often simplify the results of medicalresearch. Find out for yourself what a study really reported, and determinewhether it was based on good science. Think about the type of study.____

Watchfor misleading language. Some studies will find that a behavior “contributesto” or is “associated with” an outcome; this does not mean that a certaincourse must lead to a certain result.____ Carefully read or listen toinformation in order to fully understand it.

Useyour common sense. If a report seems too good to be true, probably it is. Beespecially careful of information contained in advertisements.____ Evaluate “scientific” statements carefully,and be aware of quackery(江湖骗术).____ Friends and family members can be a greatsource of ideas and inspiration, but each of us needs to find a healthylifestyle that works for us.

Developingthe ability to evaluate reasonably and independently about the health problemswill serve you well throughout your life.

A.The goal of an ad is to sell yousomething.

B.Make choices that are right for you.

C.And examine the findings of theoriginal research.

D.Be sure to work through the criticalquestions.

E.Distinguish between research reportsand public health advice.

F.The following suggestions can help yousort through the health information you receive from common sources.

G.Be aware that information may also beincorrectly explained by an author's point of view.