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（请给出正确答案）
_________
A.enough
B.more
C.too
D.less
B.more
C.too
D.less
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考题
下面对2mol/LNaOH溶液的叙述中，正确的是（ ）A.把2molNaOH溶于1L水所得的溶液
B.把80gNaOH溶于水并使体积为1L的溶液
C.含有2molNaOH的溶液
D.把含40gNaOH的2L溶液蒸发掉一半水所得的溶液
考题
假如你把一根大头针戳进气球，要过多久气球才会爆裂呢?不需要很久，而且这个时间可以利用高速摄像来测定。不管怎样，橡胶在压力之下裂开，总是要耗费“一点儿”时间的。然而，假定你取一个分子，它只有十亿分之四英寸大，对它完成相当于把一根针戳进气球的动作，那么这个分子要隔多久才会断裂呢?这个时间要比气球爆裂短得多，然而科学家现在照样能测出来。一个分子是由一团原子组成的。当这些原子互相靠得足够近，由于它们外层区域的微小电子相互交叠在一起，因而使这些原子粘合在一起了。这种电子的交叠形成了一种稳定状态，倾向于保持不变。为了保持这种状态，原子必须继续保持紧密相连，这就形成了所谓的“化学键”。
形成一个化学键的两个原子并不是保持静止不动的。在绝对零度（等于-273℃）以上的任何温度下，原子总是倾向于以随机的方式随意运动。不过，当它们被化学键绑在一起后，就
不能再自由运动，但可以这么说，它们仍不断地尝试做自由运动。被化学键绑在一起的两个原子可能会做相互分离的运动，但是化学键会把它们拉回到一起来。它们会再做分离运动，但又被拉回，如此往复。因此，原子就在自己的位置上振动。
化学键活像一个小弹簧，原子相互分离得越远，化学键施加的拉力就越强。然而，如果由于某种缘故，原子的分离运动超过一个临界值，化学键就会紧张过度，像一根弹簧那样，出现断裂。这时，分子断裂，而原子获释。随着温度升高，原子会逐渐远离，超过化学键的束缚。如果温度升得足够高，分子肯定会断裂。同样，如果注入其他形式的能量，分子也会趋于断裂。现在的问题是一旦注入足够的能量，分子断裂开的时间有多长。研究人员发现，一个化学键从受损到断裂所需的时间是2．05×10-17秒。光线以每秒186262英里的速度运动，这是我们宇宙中能够达到的最快速度。如果一束极快的激光脉冲打在分子上，在化学键断裂以前，这束光也只能离开四百分之一英寸。
对第二段“倾向于保持不变”的理解，正确的一项是（ ）A.这句话是指电子很不容易稳定
B.这句话是指原子很不容易稳定
C.这句话是指原子具有稳定状态
D.这句话是指化学键具有稳定状态
考题
假定你是中国文化知识大赛组委员会主席李华，写信祝贺参赛选手John Smith获得本次大赛一等奖，并通知其以下事项：
?1．出席12月10 13晚在北京友谊宾馆举行的庆祝晚会。
?2．赢得了免费中国10 13游。
?3．如果能够参加旅游，应将信中所附表格填好，并准备好护照（passport）。组委会将负责其他相关事宜。
注意：词数应为100左右
October 17th,2012
Dear Mr.John Smith,
Sincerely yours,
Li Hua
Chair
考题
Life gets noisier every day and very few people can free from noise of some sort or another.It doesn′t matter where you live--in the middle of a modem city,or a faraway village--the chances that you will be disturbed by jet aero planes,transistor radios,oil powered engines,etc.,are almost everywhere.We seem to be getting used to noise,too.Some people feel quite lonely without background music while they are working.
Scientific tests have shown that total silence can be very frightening experience for human beings.However,some people enjoy listening to pop music which is very loud,and this can do harm to their eardrums（耳鼓）.The noise level in some disco is far above the usual safety level for heavy industrial areas.
One recent report about noise and concentration（专心）suggested that although a lot of people say that any noise disturbs their concentration,what really affects their ability to concentrate is a change in the level of noise.It goes on to say that a background noise,which doesn′t change too much（music,for example）may even help people to concentrate.
"Background music"in the passage meansA.music played in the concert
B.a kind of noise coming into your ears
C.music which helps people to concentrate
D.music played while people are working
考题
Around the world more and more people are taking part in dangerous sports and activities．Of course，there have always been people who have looked for adventure--those who have climbed the highest mountains，explored（探险）unknown parts of the world or sailed in small boats across the greatest oceans．Now，however，there are people who seek（寻找）an immediate thrill（令人激动的事情）from a risky activity which may only last a few minutes or even seconds．
I?would consider bungee（蹦极）jumping to be a good example of such an aetwity．You jump?from a high place（perhaps a bridge or a hot air balloon）200 metres above the ground with an elas-tic（弹性的）rope tied to your ankles．You fall at up to 150 kilometres an hour until the rope stops you from hitting the ground．It is estimated that 2 million people around the world have now tried bungee jumping．Other activities which most people would say are as risky as bungee jumping involve（包括）jumping from tall buildings and diving into the sea from the top of high cliffs．
Why do people take part in such activities as these?Some psychologists（心理学家）suggestthat it is because life in modern societies has become safe and borin9．Not very long ago，people’s lives were constantly under threat．They had to go out and hunt for food，diseases could not easily be cured，and life was a continuous battle for survival．
Nowadays，according to many people，life offers little excitement．They live and work in?comparatively safe environments;they buy food in shops;and there are doctors and hospitals to look?after them if they become ill.The answer for some of these people is to seek danger in activities such?as bungee jumping.
More and more people today__________.A.are trying activities such as bungee jumping
B.are climbing the highest mountains
C.are coming close to death in sports
D.are looking for adventures such as exploring unknown parts of the world
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