题干

如图,取一个瓶口内径略小于乒乓球直径的雪碧瓶,去掉其底部,把一只乒乓球放到瓶口处,然后向瓶里注水,会发现水从瓶口流出,乒乓球不上浮.若用手指堵住瓶口,不久就可观察到乒乓球上浮起来.此实验说明了(  )

A:大气存在压强

B:连通器原理

C:浮力产生的原因

D:液体的压强与液体的密度和深度有关

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C

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    Have you ever found yourself in this situation:You hear a song you used to sing when you were a child-a bit of nostalgia(怀旧)or "blast from the past,"as we say.But it is not a distant childhood memory.The words come back to you as clearly as when you sang them all those years ago.

    Researchers at the University of Edinburgh studied the relationship between music and remembering a foreign language.They found that remembering words in a song was the best way to remember even one of the most difficult languages.

    Here is what they did. Researchers took 60 adults and randomly divided them into three groups of 20.Then they gave the groups three different types of "listen-and-repeat" learning conditions.Researchers had one group simply speak the words.They had the second group speak the words to a rhythm,or beat.And they asked the third group to sing the words.

    All three groups studied words from the Hungarian language for 15minutes.Then they took part in a series of language tests to see what they remembered.

    Why Hungarian,you ask ? Researchers said they chose Hungarian because not many people know the language.It does not share any roots with Germanic or Romance languages,such as Italian or Spanish.After the tests were over,the singers came out on top.The people who learned these new Hungarian words by singing them showed a higher overall performance.They did the best in four out of five of the tests.They also performed two times better than those who simply learned the words by speaking them.

    Dr.Katie Overy says singing could lead to new ways to learn a foreign language.The brain likes to remember things when they are contained in a catchy 3,or memorable 4,tune 5.

    Dr.Ludke said the findings could help those who struggle to learn foreign languages.On the University of Edinburgh's website Dr.Ludke writes,"This study provides the first experimental evidence that a listen-and-repeat singing method can support foreign language learning,and opens the door for future research in this area."