题干

某化学兴趣小组,为验证Ag、Fe、Cu三种金属的活动性顺序,设计了如图所示的实验操作,其中可以达到实验目的组合是(    )

A:①③

B:②④

C:④⑤

D:②③

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答案(点此获取答案解析)

D

同类题4

阅读下列材料,并按要求回答问题。

材料一:网络文学要紧跟时代发展,把握人民需求,以中国梦为时代主题,以爱国主义为主旋律,以中国精神为灵魂,以中华优秀传统文化为根基。中国作为历史悠久的文化资源大国,抓住了数字化传媒的时代机遇,实实在在地做成了网络文学强国。开展网络文学创作活动,适合了人民群众对文化市场和大众传媒的发展的需求,有利于推动社会主义精神文明建设。要深化马克思主义文艺观教育,引导网络文学创作、编辑、出版、传播等环节自觉践行社会主义核心价值观,培养造就一批思想、业务、道德水平高的名作家、名编辑,为网络文学繁荣持续发展提供源源不断的人才保障。

材料二:近年来,网络文学迅速发展,已成为我国数字出版产业的重要组成部分和网络文艺的重要类型,广受众多文学爱好者及青少年喜爱。同时必须看到,目前网络文学也存在数量大质量低、抄袭模仿、市场主体良莠不齐等问题。传统文学由于严格的审稿制度和报刊杂志审查制度,使有关题材不能涉及。网络文学的题材更加丰富,只要在政治上不违法乱纪,许多传统文学不能涉猎的内容都可以表现。网络作家要要站在人民的立场、用人民的“眼睛”观察时代和认识生活,分清事物的本质与现象、主流与支流、光明与黑暗,正确描写时代变化、社会发展、民族进步,为时代和社会提供正能量。

同类题5

完形填空

    I had just arrived in this Asian country for a one-year teaching position. One day, I took the subway to visit some ancient palaces and temples in the downtown. The following account of what happened to me has taught me much about culture 1.

    Since all the 2 were taken, I stood. Suddenly, I felt someone pulling on my bag. 3 I probably was in someone's way, I moved over slightly. But in one quick motion(动作), I felt my bag removed from my back, and in a flash it was 4. I turned around to see who the thief was. I looked at the people standing behind me, but didn't see my bag or any 5. My heart sank and I began to 6.

    I glanced around the car only to find directly across from me was an elderly lady, and sitting on her lap was my 7. I tried to get it back from her lap. But as I began to 8 it up, she quickly grabbed(抓住) it back and held onto it. I looked around at the people standing beside me, and those sitting beside her, but no one took any 9 of the situation. Trying not to cause a(an) 10, I tried to negotiate through gestures. I used my hands as best as I could, but she 11 my requests for my bag and pointed to my back. She picked up my bag, showing how 12 it was. I finally began to understand. She was holding my bag to13 me.

    At the next stop, a middle-aged woman got on the crowded subway. Another elderly woman sitting down took her bag, 14 it on her lap. They didn't talk; 15 this older woman was more than pleased to sit with this stranger's bag on her lap throughout her journey.

    As the subway pulled into the main downtown station and I was getting ready to get off, the woman 16 handed me back my bag. But 17 I had a chance to thank her, she had disappeared into the crowd.

    Sadly, this considerate custom was more 18 to me than if I had been robbed. Everyone back home had heard of being robbed—that was 19 city behavior—but having a stranger hold onto someone's bag out of 20, in a city of twelve million people—that was truly unusual.