题干

如图是甲、乙、丙三种固体物质的溶解度曲线,下列说法错误的是(   )

A:将相同质量甲、乙的饱和溶液从t3℃降到t2℃,析出甲的质量大

B:t2℃时,甲和乙的饱和溶液各100g,其溶质的质量一定相等

C:分别将t3℃时甲、乙、丙的饱和溶液降温至t1℃,则所得的三种溶液中溶质的质量分数大小关系是乙>甲>丙

D:t1℃时,丙的饱和溶液中溶质的质量分数为40%

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D

同类题1

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    According to findings of a survey by Citi and Seventeen Magazine, nearly four out of five (almost 80 percent) college students work while attending college, with the average work load of 19 hours per week. But should college students work while at college? Many factors should be considered.

    One benefit of working while in college is that it can help build your resume, regardless of whether the job is in your field, according to an article at Scholarships.com. "If you're lucky enough to find a job that closely relates to your major, you could get a leg up on the rest of your class once you graduate, because you'll have more experience in your chosen field," according to the article.

    Perhaps the most compelling reason for working while earning a degree is the money. While it's unlikely to entirely finance your education through a part-time or full-time job, you can still make quite a dent(削减)in the college bill by working.

    But some students prefer not to work while earning a degree so they can focus on getting the best grades. It's true that you'll have more time to stay at school if you don't work, provided you use that time wisely. If you feel like even 10-15 hours a week of work will hurt your grades, then perhaps you should not consider working.

    Working a part-time or full-time job can take away time from social activities, according to a You University TV article. "Trying to balance a job and your college studies, and taking a job can cut down your time to hang out with friends," according to writer Dave Potts.

    In addition to missing out on hanging out with your friends, working during college could prevent you from attending a number of campus events, such as movies on the lawn or football games. While you may be able to land a job that's flexible, it seems unlikely they'll let you choose your own schedule.

    So should students work at college? The decision should be made on a case-by-case basis. Some students can also thrive in school while working, whereas others can't.

同类题2

阅读下文,回答相关问题。

                                                                              我在寻找那片野花
       上小学的时候,班上有个女同学,叫做荞,家境贫寒,她衣着破烂,夏天总穿短裤,是捡哥哥剩下的。
        我和她同期加入少先队。那时候,入队仪式很庄重。新队员的红领巾,是提前交了钱买下的。荞说她没有钱,哥哥已超龄退队,她可用哥哥的旧领巾。授巾的仪式那天,当辅导员用托盘把新领巾呈到校长手中时,就提醒校长记得把托盘里的那条旧领巾分给她。
     (A)满盘的新领巾好似一塘金红的鲤鱼,支棱着翅角。旧领巾软绵绵地卧着,仿佛混入的灰鲫,落寂孤独。
       校长可能不曾听清这句格外的交待,走到荞的面前时,随手把一条新领巾分给了她。我看到荞好像被人砸了一下头顶,身体矮了下去。灿如火苗的红领巾环着她的脖子,也无法映暖她苍白的脸庞。
       那个交了新红领巾的钱,却分到一条旧红领巾的女孩,委屈至极。刚一散会,就怒气冲冲地跑到荞跟前,一把扯住荞的红领巾说:“这是我的!你还给我!”领巾是一个活结,被女孩拽住一股猛挣,就系死了,好似一条绞索,把荞勒得眼珠凸起,喘不过气来。大伙扑上拉开她俩。荞满眼都是泪花,窒息得直咳嗽。
        我们都觉得那女孩太霸道了。荞一声未吭,把新领巾折得整整齐齐,还了它的主人。把旧领巾系好,默默地走了。
        后来我问荞,她那样对你,你就不伤心吗?荞说,谁都想要新领巾啊,我能想通。
        毕业的时候,荞的成绩很好,可以上重点中学。但因为家境艰难,只考了一所技工学校,以期早早分担父母的窘困。荞以后的路,就一直在贫困的底层挣扎。
        荞是一家印刷厂的女工。早几年,厂子还开工时,她送过我一本交通地图。说是厂里总是印账簿一类的东西,一般人用不上的。碰上一回印地图,她赶紧给我留了一册,想我有时外出,或许会用得着。说真的,正因为常常外出,各式地图我很齐备。但我还是非常高兴地收下了她的馈赠。我知道,这是她能拿得出的最好的礼物了。
        一次聚会,荞终于来了。她所在的工厂宣布破产。她成了下岗女工。她的丈夫出了车祸,伤了腿,从此吃不得重力。儿子得了肝炎休学,需要静养和高蛋白。她在几地连做小时工,十分奔波辛苦。这次刚好到这边打工,于是抽空和老同学见见面。我们都不知说什么好,只是紧握着她的手。(B)她的掌上有很多毛刺,好像一把尼龙丝板刷。
        半小时后,荞要走了。同学们推我送送她。我打了一辆车,送她去干活的地方。本想在车上,多问问她的近况,又怕伤了她的尊严。正斟酌为难时,她突然叫起来:“你看!你快看!”
       窗外是城乡交界部的建筑工地,尘土纷扬,杂草丛生,毫无风景。我不解地问,你要我看什么呢?
荞很开心地说,我要你看路边的那一片野花啊。每天我从这里过的时候,都要寻找它们。我知道它们哪天张开叶子,哪天抽出花茎,在哪天早晨,突然就开了……我每天都向它们问好呢?
       我一眼看去,野花已风驰电掣地闪走了,看到的只是荞的脸,憔悴之中有了花一样的神采。于是,我那颗久久悬起的心,稳稳地落下了。我不再问她任何具体的事情,彼此已是相知。人的一生,谁知有多少艰涩在等着我们?(C)但荞经历了重重风雨之后,还在寻找一片不知名的野花,问候着它们。我知道在她心中,还贮备着丰足的力量和充沛的爱,足以抵抗征程的霜雪和苦难。
        此后我外出的时候,总带着荞送我的地图册。 (选自《写给女儿们的散文》)