题干

西瓜堪称“瓜中之王”, 是葫芦科双子叶开花植物,原产于非洲,唐代引入新疆,五代时期引入中土。关于西瓜的叙述,正确的是(  )

A:西瓜属于被子植物,有双受精现象,胚乳提供胚萌发所需的养料

B:在结构层次上,西瓜属于果实,瓜瓤和瓜皮都是子房壁发育成的

C:在西瓜迅速膨大的季节,植株吸收的水分大多进入细胞的液泡中

D:西瓜脂肪含量低,含糖量高,这些成分主要在胃和小肠中被吸收

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B

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    Which comes first, happiness or money? Are richer people1? And 2how do people get richer? A recent study could tell you the answer.

    The study3thousands of teenagers and found that those who felt better about4as young adults 5 to have higher incomes by the time they 629. Those who were happiest earned an average of $8,000 more than those who were the most7.

    The researchers, from University College London and the University of Warwick, say that very gloomy(沮丧的)teens, no matter how tall or smart they were, earned 10% less than their peers8the happier ones earned 930% more.

    Happier teenagers have an easier time 10school, college and the job 11,12 because they always feel better about life. It may13 be true that happier people find it easier to make friends, who are often the key to homework help or networking.

    A report in June suggested that professional respect was more important than14in terms of workplace happiness. In August scientists announced that they had found the 15for happiness in women. Alas! The same gene doesn't appear to have16effect on men. And in October researchers in the UK and in the US announced that people who eat seven portions of fruit and vegetables a day report being the happiest.

    If it is really true that happier kids17being wealthier kids, is it necessary for parents to get their kids to do the homework? The fact is that 18 homework will make kids happy but surely hurt their grades. Studies do show19 that more education20better-paid jobs, which may give us a deep thought.