题干

甲商品价格(P甲)与乙商品需求量(Q乙)之间存在如图所示关系。在其他条件不变的情况下,下列判断正确的是

①甲商品价格上涨时,乙商品的需求量增加
②甲乙商品的需求量与价格能够相互影响 
③甲乙商品组合在一起才能满足人们的需要
④甲商品处于买方市场,乙商品处于卖方市场

A:①②

B:②③

C:③④

D:①④

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答案(点此获取答案解析)

B

同类题1

阅读下文,完成下列小题。

人生因阅读而气象万千

    ①每至世界读书日,这样一张照片所定格下的历史瞬间总会被人提起:1940年10月22日,英国遭受空袭,位于伦敦的荷兰屋图书馆也难以幸免,几乎被炸成废墟,墙壁倾颓,砖石满地,但有3名男子竟不顾敌机刚刚离去,又在尚未倒塌的书架前翻捡书籍,战火的残酷与读书所展现的不屈意志,两相对比,不仅给人以强烈的视觉冲击,更给人以持久的感动。

    ②或许,也会有人不解:战火纷飞,还不忘阅读,为的是什么?“很多人被生活的艰难折磨得心灵枯萎,但有书香滋润的灵魂不会.”不久前,在一家书店里看到的一则读者留言,或许可以作为解答,对于那3名男子而言,阅读绝非是暂时忘记战乱的“镇定剂”,而是勇敢面对现实,让精神再次振奋、让意志战胜泪水的方法和途径。

    ③阅读何以有这样的伟力?一位作家曾指出,阅读实际上会给人以两种收获,一种是通过读书,知道自己原来不知道的东西;另一种是通过读书触发反思,知道自己本来就有的东西,并激活它,前者是知识,后者是智慧。越是走在人生的“三岔口”,越是面临国难和选择之时,阅读的力量就越能显示出来,一个人的努力往往会让自己有更多的选择,知识让我们理解每一项选择的意义,而智慧还能进一步让人知道,自己的选择是符合内心的,从而坚定前行的意志。

    ④人生如果远离了阅读,就等于一间房子没有窗户。曾国藩一生饱览群书,文章笔力雄厚,就连梁启超都称赞他“可以入文苑传”。然而,即使有如此深厚的功底,他依然认为自己有“三耻”,居第一位的,就是对天文和算学“毫无所知”。一物不知,便深以为耻,曾国藩们之所以会有如此的认识,就因为他们深刻地知道,读书“能养人精神”,书籍并非是装点门面的饰品,与是精神的营养品。不能与书籍独处,只会让人生之路走向狭隘,甚至禁锢心灵;浸润书香,才能让我们驶向无限广阔的海洋。

    ⑤读书或许并不必然导向外在的成功,但它必然指向内在的丰沛。这些年,两季《中国诗词大会》的冠军,惊艳了无数人,一位是第二季的武亦姝,另一位是第三季的雷海为,令人动容的,并不仅仅是武亦姝2000多首诗词记忆量的才情,也不全是雷海为以外卖小哥身份成功逆袭的不凡,更是因为他们身上散发的那种“闲看花开花落,漫随云卷云舒”的从容淡定,这样一份独特的气质,正源于阅读的滋养,有句话说得好,“读书多了,容颜自然改变,许多时候,自己可能以为许多看过的书籍都成过眼烟云,不复记忆,其实它们仍是潜在的,在气质里、在谈吐上、在胸襟的无涯,当然也可能显露在生活和文字中。”

    ⑥有人以为,读书太多,容易脱离生活,其实不然,读书不是要选离这个世界,而是要让人拥有平视世界的眼睛,阅读本身就是为了更好地生活,正如哲人所言,“一个人和书籍接触得愈亲密,他便愈加深刻地感到生活的统一,因为他的人格复化了,他不仅用他自己的眼睛观察,而且运用着无数心灵的眼睛。”既塑造丰盈的内心,又给人以丰富的生活,这恐怕便是阅读之于人生的独特意义。(有删改)

同类题4

阅读理解

    We produce 500 billion of plastic bags in a year worldwide and they are thrown away polluting oceans, killing wildlife and getting dumped in landfills where they take up to 1,000 years to decompose. Researchers have been unsuccessfully looking for a solution.

    The 16-year-old Canadian high school student, Daniel Burd, from Waterloo Collegiate Institute, has discovered a way to make plastic bags degrade(降解) in as few as 3 months, a finding that won him first prize at the Canada Wide Science Fair, a $10,000 prize, a $20,000 scholarship, and a chance to revolutionize a major environmental issue.

    Burd's strategy was simple: Since plastic does eventually degrade, it must be eaten by microorganisms(微生物).If those microorganisms could be identified, we could put them to work eating the plastic much faster than under normal conditions.

    With this goal in mind, he grounded plastic bags into a powder and concocted(调制) a solution of household chemicals, yeast(酵母) and tap water to encourage microbes growth.Then he added the plastic powder and let the microbes work their magic for 3 months.Finally, he tested the resulting bacterial culture on plastic bags, exposing one plastic sample to dead bacteria as a control.Sure enough, the plastic exposed(暴露) to the live bacteria was 17% lighter than the control after six weeks.

    The inputs are cheap, maintaining the required temperature takes little energy because microbes produce heat as they work, and the only outputs are water and tiny levels of carbon dioxide.

    “Almost every week I have to do chores and when I open the closet door, I have piles of plastic bags falling on top of me.One day, I got tired of it and I wanted to know what other people are doing with these plastic bags.The answer: not much.So I decided to do something myself.” Said Daniel Burd.