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[单选题]
Only (within) the past 200 years (scientists have) found (out what) fire (is).
A.within
B.scientists have
C.out what
D.is
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题目内容
（请给出正确答案）
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题目内容
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A.within
B.scientists have
C.out what
D.is
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更多“Only （within) the past 200 yea…”相关的问题
A. within
B. at
C. by
D. with
(i) Cost of transporting the plant to the factory
(ii) Cost of installing a new power supply required to operate the plant
(iii) A deduction to reflect the estimated realisable value
(iv) Cost of a three-year maintenance agreement
(v) Cost of a three-week training course for staff to operate the plant().
A、(i) and (ii) only
B、(i), (ii) and (iii)
C、(ii), (iii) and (iv)
D、(i), (iv) and (v)
In the early fifties, only eight or nine out of a hundred young men changed their jobs within the first three years with the company. In the past few years, almost thirty-five percent of the college-graduated work force changed jobs within the same period. These people want to intensify their management training. Since most jobs take only a year to a year and a half to master, in order to continue learning, they have to make a job change. Even company presidents tend to be seen as mobile specialists, staying with one company an average of only five years.
Company presidents in the United States today tend to be young men who begin their careers with educational backgrounds in engineering science, or business management. They have worked for a few years as technical specialists and quickly moved into higher management positions. Most of them were making ＄ 30 000 per year by the time they reached thirty. On an average, these men have only twenty years working experience at management level when they become company presidents. On the way to the top, they have an average of eleven promotions and seven city transfers.
Friendships remain casual and are usually derived from business contracts. Families of these career men have little time to put down roots in and become part of a community.
In the past, a few men attained high positions through family and social connections; today, high positions go to men who are mobile, and have good educational, backgrounds.
According to the passage, an increasing number of future company presidents might be ______.
A．people who have spent a number of years with one company
B．young people who do not want to move often, but are steady and dependable
C．people who have spent a long time concerned with community affairs
D．young people who have good education and are willing to move around
One ShotSpotter covers a square mile. Eight microphones are put on the roofs of buildings. These microphones pick up gunfire noise. It only takes seven seconds to report the gunfire to the police. Then a red dot on the police map shows where the action is.
The ShotSpotter really works well. It locates the gunfire within 20 to 40 feet plus or minus. Redwood City police are very happy with the ShotSpotter. They think it might have helped catch the D.C. sniper.
ShotSpotters cost a lot of money. One of them sells for $200,000. Despite the cost, ShotSpotters can be a big help in fighting crime.
Eight microphones placed on rooftops ______.
A．talk to police
B．warn the public
C．listen for gunfire
D．play rap music
Of course, some people have remarkable chances which lead to fame and success without this long and hard training. Connie Pratt, for example, was just an ordinary girl working in a bicycle factory. A film producer happened to catch sight of her one morning waiting at a bus stop, as he drove past in his car. He stopped and asked if she would like to go to the film studio to do a test, and she thought he was joking. It took the producer twenty minutes to convince Connie that he was serious. The test was successful. And within a few weeks she was playing the leading part opposite one of the most famous actors of the day. But chances like this happen once in a blue moon!
From the very beginning, the author puts it clearly that acting is a profession______.
A．for ambitious people only
B．for young people only
C．too difficult for young people
D．sought after by too many people
Your friends are always【79】for an informal chat or an evening's entertainment. The【80】exhibitions, films or plays are always within easy reach. Shopping, too, is always a pleasure. But what about the hustle and bustle of city life？ The city dweller neverhas a moment【81】peace; he is always【82】. And what about the noise and pollution of the city？ Day and night the city is in uproar with its unceasing traffic. The air is polluted with poisonous gases emitted by the smokestacks of factories.
Country life is in many aspects【83】city life. For one thing, the people there are friendly. People are【84】with one another. You can never【85】receive a friendly nod or a kind word from anyone you chance to meet.
(76)
A．enjoyable
B．exciting
C．experienced
D．unpleasant
During the past 200 years the world population has increased 6 times, the annual world output has increased 80 times, and the distance a person can travel has gone up 1,000 times. There has also been much recent progress in art, culture, learning, and science. Such changes have led to a high rate of production and growth of the economy.
Economists fear that within the next 100 to 150 years, the earth's resources will become very scarce. Their fears are partly justified, but we should not be afraid. Industrial civilization adapts to new knowledge. By advancing knowledge, we not only create new forms of resources, but we also find ways to economize their use. Advanced modern knowledge can feed the hungry people of the world and improve their standard of living.
The figures in the second paragraph are used for the following purposes EXCEPT______.
A．prediction.
B．contrast.
C．definition.
D．explanation.
Once people believed it was 19) that the human brain was fully developed by the age of three. According to this theory, teenager behaviors like risk-taking, a lack of sensitivity to how their actions 20)both themselves and others, increased aggressive deeds, 21) concentration and a negative attitude were thought to be due to bad parenting or changes in body chemistry.
However, new technology has allowed researchers to examine the healthy brain at work. What they have discovered is something 22) : Not only does the brain continue to grow beyond the age of three, but the research also23) that the brain of a teenager is larger than that of an adult.
As teen brains are 24) with chemicals during adolescence phase, the brain grows. However, only the cells that are used the most will 25) the competition within the brain. Those that are used less begin to die off until the brain reaches what will be its adult size.
The way that teens spend their time 26) influences which connections remain and which disappear. On the basis of this knowledge, experts advise parents to be 27) on how their teenagers spend their time. What teens do today will affect their brains for the rest of their lives.
A) diminished
B) demonstrated
C) alert
D) radical
E) surrender
F) survive
G) affirms
H) afford
I) affect
J) effect
K) soaked
L) soaped
M) sensitive
N) sensible
O) somehow
