单项选择题：在Visual FoxPro中，建立索引的作用之一是A．节省存储空间 B．便于管理

题型：选择题

用氯酸钾和二氧化锰加热制氧气，反应完毕后，二氧化锰和氯化钾的质量之比为1：2，反应开始时氯酸钾和二氧化锰的质量之比为（　　）

A．245：87

B．329：100

C．490：149

D．87：149

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题型：阅读理解

"Yes, but what did we use to do before there was television?" How often we hear statements like this! Television hasn't been with us all that long, but we are already beginning to forget what the world was like without it. Before we admit the one-eyed monster into our homes, we never found it difficult to occupy our spare time. We used to enjoy civilized pleasures. For instance, we used to have hobbies, we used to entertain our friends and be entertained by them, we used to go outside for our amusements to theaters, cinemas, restaurants and sporting events. We even used to read books and listen to music and broadcast talk occasionally. All that belongs to the past. Now all our free time is regulated by the "goggle-box". We rush home or gulp down（吞咽）our meals to be in time for this or that program. We have even given up sitting at table and having a leisurely evening meal, exchanging the news of the day. A sandwich and a glass of beer will do-anything providing it doesn't interfere with the program. The monster demands and obtains absolute silence and attention. If any member of the family dares to open his mouth during a program, he is quickly silenced.

The whole generations are growing up addicted to the telly (television). Food is left uneaten, homework undone and sleep is lost. The telly is universal pacifier（抚慰者）．It is now standard practice for mother to keep the children quiet by putting them in the living-room and turning on the set.It doesn’t matter that the children will watch rubbishy commercials or violence－so long as they are quiet.

There is little limit to the amount of creative talent available in the world. Television consumes vast quantities of creative work. That is why most of programs are bad: it is impossible to keep pace with the demand and maintain high standards as well. When millions watch the same programs, the whole world becomes a village, and society is reduced to the conditions which obtain in preliterate（无文字的）communities. We become completely dependent on the two most primitive media of communication: pictures and the spoken word.

Television encourages passive enjoyment. We become content with secondhand experiences. It is so easy to sit in our armchairs watching others working. Little by little, television cuts us off from the real world. We got so lazy; we choose to spend a fine day in semi-darkness, glued to our sets, rather than go out into the world itself. Television may be a splendid medium of communication, but it prevents us from communicating with each other. We only become aware how totally irrelevant television is to real living when we spend a holiday by the sea or in the mountain, far away from civilization. In quiet, natural surroundings, we quickly discover how little we miss the repetitive oppression of King Telly.

小题1:According to this passage, which of the following statements is NOT true?

A．We used to have hobbies and go to theaters and sporting events.

B．We have a leisurely evening meal and exchange the news when we watch TV.

C．We quickly finish our meals so as to be in time for TV programs.

D．We are usually silent and attentive in front of TV.小题2: The main idea of the second paragraph is to show that_____.

A．children are very noisy

B．TV is full of rubbishy commercials or violence

C．television disturbs our sleep

D．the whole generations are fascinated with TV小题3:Which is the best title for this passage?

A．Television Encourages Passive Enjoyment

B．Television Is Doing Irreparable（不能挽回的）harm

C．Television Is a Universal Pacifier

D．We Can't Live Without TV小题4:This passage is an article of_____.

A．narration

B．description

C．criticism

D．argumentation

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题型：计算题

在所有能源中核能具有能量密度大、区域适应性强的优势，在核电站中，核反应堆释放的核能被转化为电能，核反应堆的工作原理是利用中子轰击重核发生裂变反应，释放出大量核能。

(1)核反应方程式是反应堆中发生的许多核反应中的一种，为中子，X为待求粒子，a为X的个数，则X为_______，a=_______，以m_U、m_Ba、m_Kr分别表示、、核的质量，m_n、m_p分别表示中子、质子的质量，c为光在真空中传播的速度，则在上述核反应过程中放出的核能△E=_______。