题目内容

某企业实施质量改进项目,采用网络图法。根据所搜集的资料绘制的网络图如图6.4-6所示。根据图形可分析出: 网络图中的“虚作业”是指( )。

A. 不占时间
B. 指明先后作业前进方向
C. 先后作业有逻辑关系
D. 省略作业时间

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You can tell age of a tree by counting its rings. But these records of a tree’s life really say a lot more. Scientists are using tree rings to learn what’s been happening on the sun’s surface for the last ten thousand years. Each ring represents a year of growth. As the tree grows, it adds a layer to its trunk, taking up chemical elements from the air. By looking at elements in the rings from a certain year, scientists can what elements were in the air that year. Dr. Stevenson is analyzing one element, carbon-14, in rings from both living and dead trees. Some rings go back almost ten thousand years to the end of the Ice Age. When Stevenson followed the carbon-14 track back in time, he found carbon-14 levels changed with the intensity of solar buring. You see, the sun has cycles. Sometimes it burns fiercely, and at other times it’s relatively calm. During the sun’s violent periods, it throws off charged formation of carbon-14 on earth. When there is more solar wind activity, less carbon-14 is produced. Ten thousand years of tree rings show that the carbon-14 level rises and falls about every 420 years. The scientists concluded that solar wind activity must follow the same cycle. When the sun burns fiercely, ()carbon-14 is produced.

A. less
B. more
C. no
D. much

In spite of all stories of prosperity in the United States, not only does poverty exist there, but crimes of various types have been increasing at alarming rate. Most acts of violence were committed by young people . 57% of the criminals arrested in 1979 were youths below 25 of age.Everyone agrees that crime is party a result of bad material conditions: poverty, lack of education, living without a settled home, being parentless, sufferings from other kings of misfortune, etc.There are also other factors than material conditions which are responsible for the sharp increase of crime rate. In the first place, some state laws provide a death penalty but some protection. It is therefore possible and easy for anyone in the country to get a gun.Finally, there has been too much shown on TV and too much reported in newspaper of all kinds of crimes-the details of which are so accurately described that even children know how to duplicate what they have seen or read. All there have resulted in a high frequency of crimes committed both by professional criminals and by nonprofessional ones in murder, drug smuggling, robbery, etc. The underlined word “penalty” is closest in meaning to()

A. punishment
B. trial
C. accusation
D. execution

In spite of all stories of prosperity in the United States, not only does poverty exist there, but crimes of various types have been increasing at alarming rate. Most acts of violence were committed by young people . 57% of the criminals arrested in 1979 were youths below 25 of age.Everyone agrees that crime is party a result of bad material conditions: poverty, lack of education, living without a settled home, being parentless, sufferings from other kings of misfortune, etc.There are also other factors than material conditions which are responsible for the sharp increase of crime rate. In the first place, some state laws provide a death penalty but some protection. It is therefore possible and easy for anyone in the country to get a gun.Finally, there has been too much shown on TV and too much reported in newspaper of all kinds of crimes-the details of which are so accurately described that even children know how to duplicate what they have seen or read. All there have resulted in a high frequency of crimes committed both by professional criminals and by nonprofessional ones in murder, drug smuggling, robbery, etc. Besides bad material conditions,() also leads to the sharp increase of crime rate.

A. poverty
B. being parentless
C. lack of education
D. easy access to guns

Happiness is (21) everyone looks for. Maybe someone says that he is (22) . However, what makes him happy may not (23) for Others. And even worse, someone may spend all his (24) looking for happiness, but in vain(徒然).In the past, I tried my best to (25) myself happy. I thought if I could freely get and do what I wanted to, I (26) be happy. Certainly, it was possible but I was (27) Though I could be happy at times, I couldn’t keep my happiness for a long time. Why One day, when I told a friend of mine what I (28) about happiness, he smiled and said only a few words, "Happiness is not a single thing but a by- product(副产品)." I was surprised, but he was really (29) Someone thinks money can (30) everything, but when he becomes a millionaire after his work, perhaps he (31) find that he has new (32) . And he has to go to church for(33) . Sometimes love can bring happiness, (34) at other times it (35) misunderstanding, tiredness, and even quarrelling. Happiness is only a by-product of all (36) of things you love to do. You can not grasp it in a (37) way. That is, it is not a thing existing in material form but in your senses. You should tell yourself, "I do not (38) whether I’m happy or not. But I must love my life." And one day you will suddenly find happiness (39) has quietly (40) . 22()

A. upset
B. happy
C. sad
D. tired

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