题干

如图为甲、乙、丙三种固体物质在水中的溶解度曲线,下列说法错误的是(   )

A:t2℃时甲、乙两物质的溶解度相等

B:温度大于t2℃时,甲、乙、丙三种固体物质溶解度大小关系是甲>乙>丙

C:当甲中混入少量乙时,可用冷却热饱和溶液的方法得到较纯净的甲

D:t2℃时甲、丙两物质的饱和溶液降温到t1℃时,二者所得溶液的溶质质量分数一定相等

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答案(点此获取答案解析)

D

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阅读理解

    From the loss of wildlife to rising sea levels, we're all well aware of the problems that climate change could cause.

    But while it may seem like such issues won't affect most of us directly,it looks like future generations could grow up without something that many of us now take for granted: chocolate.

    According to an essay published by the US National Oceanic and Atmospheric Administration, changes to the climate in the regions that produce cacao - the plant from which chocolate is produced - may mean that it will soon become extinct.

    Most of the world's cacao grows in countries close to the equator,with over half of it growing in the African nations of Ghana and Ivory Coast.

It's predicted that by 2050, climate change will have accelerated the rate at which temperatures in these countries rise, making it extremely difficult for cacao to grow there.

    The problem doesn't lie in increased heat, however,but in lower humidity (湿度),as it's believed that rainfall will stay at the same level if the temperature rises.

    “In other words, as higher temperatures squeeze more water out of soil and plants, it's unlikely that rainfall will increase enough to offset the moisture (含水量) loss,” Michon Scott, the essay's author, wrote.

    To help fight this problem, researchers from Berkeley University in the US are working on changing the DNA of cacao plants to allow them to survive in dryer conditions by using gene editing technology, according to US News.

    In the meantime, US company Mars, one of the world's biggest manufacturers of chocolate products, announced in January that it would spend $1 billion to help reduce the effects of climate change.

    “This is a world issue, and it requires everyone to work together,” Mars spokesperson Barry Parkin told Business Insider.

    The message here is that if we all do our part, we may be able to prevent some of the worst impacts of climate change. Or if we're unlucky, chocolate will become a thing of the past.

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    1938年春,台儿庄战役打响。面对日军的凶猛进攻,负责指挥作战的李宗仁和白崇禧邀请周恩来到其寓所,共话战局,并在之后的作战中,基本遵循周恩来的建议。李宗仁指挥战前一向都拥兵自重的“杂牌军”在枪林弹雨中浴血奋战,他们放下成见,放下自私,携手共赴国难;中共则组织鲁南老百姓,冒着炮火,把大刀、弹药、粮食、蔬菜、肉蛋、烧酒、食盐等送上前线,再将大批伤病员运往后方救治。…… 六里石村,百多户人家,只不过是京杭大运河畔的小村落,却是大战时的后勤基地之一,一桶桶开水,一罐罐小米稀饭从这里送往前线。时年23岁的美国合众社战地记者爱泼斯坦赴台儿庄前线,他在1939年出版的《人民之战》中记载:她去台儿庄城之前,有个10岁的中国男孩被日军胁迫到中国守军阵地侦查,在随后的炮击中,中国守军都很困惑,日军向空旷的原野上倾洒了那么多的炮弹,为什么?原来,这名10岁的孩童向日军汇报时,故意颠倒了中国守军的方位……             ——摘编自《南方周末》2015年4月9日第1624期《抗战地理二》请回答: