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The final goal of designing a lens is______.
A．to trap the opponent's lenses
B．to focus light with lenses
C．to hand-make lenses at low cost
D．to reflect light by means of curved surfaces
答案
更多“The final goal of designing a lens is______.A．to trap the opponent's lensesB．to focus ligh”相关的问题
第1题
“Shadowland” in the last sentence refers to ________.
A) the wonderland one often dreams about
B) the bright future that one is looking forward to
C) the state of uncertainty before one’s final goal is reached
D) a world that exists only in one’s imagination
第2题
The lens designer has one enormous advantage over the chess player: the designer is free to call on any available source of help to guide him through the staggering number of possibilities. Most of that help once came from mathematics and physics, but recently computer technology, information theory, chemistry, industrial engineering and psychophysics have all contributed to making the lens designer's job immeasurably more productive. Some of the lenses on the market today were inconceivable a decade ago. Others whose design is as much as a century out can now be mass-produced at low cost. With the development of automatic production methods, lenses are made by the millions, both out of glass and out of plastics. Today's lenses are better than the best lenses used by the great photographers of the past. Moreover, their price may lower, in spite of the fact that 19th-century craftsmen worked for only a few dollars a week and today's lenses are more complex. The lens designer cannot fail to be grateful for the science and technology that have made his work easier and his creations more widely available, but he is also humbled: it is no longer practical for a fine photographic lens to be designed from beginning to end by a single human mind.
Lens design and chess playing are similar in that______.
A．the final goal and the means by which it can be reached are known
B．perfect solutions to a problem can be found
C．any one decision at any point along the way to the goal can bring numerous possible results
D．both A and C
第3题
Designing a lens can be compared to playing chess. In chess a player tries to trap his opponent's king in a series of moves. In creating a lens a lens designer attempts to “trap” light by forcing all the rays arising from a single point in the subject to focus on a single point in the image, as a consequence of their passing through a series of transparent(透明的) elements with precisely curved surfaces. Since in both cases the ultimate goal and the means by which it can be attained are known, one is tempted to think there will be a single best decision at any point along the way. The number of possible consequences flowing from any one decision is so large, however, as to bevirtually, if not actually, infinite. Therefore in lens design, as inchess, perfect solutions to a problem are beyond reach. Although this article will be concerned only with the design of photographic lenses, the same principles apply to all lenses.
The lens designer has one enormous advantage over the chess player: the designer is free to call on any available source of help to guide him through the staggering number of possibilities. Most of that help once came from mathematics and physics, but recently computer technology, information theory,chemistry, industrial engineering and psychophysics have all contributed to making the lens designer's job immeasurably more productive. Some of the lenses on the market today were inconceivable a decade ago. Others whose design is as much as a century old can now be massproduced at low cost. With the development of automatic production methods, lenses are made by the millions, both out of glass and out of plastics. Today's lenses are better than the best lenses used by the great photographers of the past.Moreover, their price may lower, in spite of the fact that 19thcentury craftsmen worked for only a few dollars a week and today's lenses are more complex. The lens designer cannot fail to be grateful for the science and technology that have made his work easier and his creations more widely available, but he is also humbled: it is no longer practical for a fine photographic lens to be designed from beginning to end by a single human mind.
Lens design and chess playing are similar in that ____
A) the final goal and the means by which it can be reached are known
B) perfect solutions to a problem can be found
C) any one decision at any point along the way to the goal can bring numerous possible results
D) both A and C
根据阅读材料回答问题。本题为单选题，请给出正确答案及解析，谢谢！
第4题
Final stars under microscope
At the kick-off of Wednesday evening's UEFA Champions League final, there were 16 players on the Stade de France turf whose next assignment will be in Germany in June.
With little over three weeks before the start of the FIFA World Cup, the match duly offered FIFA-worldcup, cons an ideal last chance to assess the form. of some of the summer's likely headline-makers.
Jens Lehmann(GER, Arsenal)
It is net easy to evaluate a player who spent only 18 minutes on the pitch. In this highly limited time span, the Mannschaft's first-choice keeper was only called upon to repel a couple of straightforward shots, one from Ludovic Giuly and the other from Deco. That said, his first goal-kick was wayward and with his confidence affected, he then restricted himself to short passes to his defenders. Caught out in a one-on-one with Samuel Eto'o, Lehmann was rightly dismissed for felling his opponent and watched the majority of the match from the stands.
Carlos Puyol(ESP, Barcelona)
For a long time, it looked as though Thierry Henry would never succeed in shaking off his shaggy-haired marker. Solid and tigerish, the Spanish central defender allowed the Arsenal striker very little space for the first hour of the game. But as time went on, he seemed to increasingly struggle to keep up with the Gunners' attacks. No doubt his long and punishing season has caught up with him, but a few weeks' rest should see him restored to his best in time for Germany.
Rafael Marquez(MEX, Barcelona)
While always precise and effective with the ball at his feet, the Mexican defender was regularly troubled by the pace of Henry. Rescued by his goalkeeper in the third minute after being caught flat-footed by the French striker, he could have been sent off a few moments later for a tackle front behind that caught the same player on the ankle. Like Puyol, he was guilty of allowing opposing players to get in be- hind him too often during the second half.
Giovanni van Bronckhorst(NED, Barcelona)
Although excellent on the counter, the Dutchman is not really a natural defender. Always looking to get forward, he has a tendency to drift from his left-back position into a more advanced role. You would not want to change him too much, though, for just like Marco van Basten's Orange side, Barcelona got considerable rewards from his forward forays. Moreover, he never stopped running until the final whistle.
Emmanuel Eboue(CIV, Arsenal)
Cote d'Ivoire has one of the best right-backs in the world. Active, willing and technically adept, Eboue left a really positive impression on the Stade de France crowd. Hurt in a first-half clash with Giovanni van Bronckhorst, he seemed to struggle somewhat after that, but the fact that Samuel Eto'o and Ronaldinho-whom he found himself up against most often-shone only fleetingly was to a large extent down to him. The only feature of his game that might work against him in Germany is an unwelcome tendency to complain.
Kolo Toure(CIV, Arsenal)
The linchpin of Arsenal's defence, Kolo Toure is one player who can justifiably feel hard done by at having lost this final. So sparkling was his individual perfromance that, whether faced by Ronaldinho, Eto'o or Henrik Larsson, the Ivorian always looked comfortable. Invariably positioned in the ideal spot, Toure seemed to be omnipresent(无所不在的) on the pitch. His understanding with countryman Eboue is a big plus for club and country and he is sure to be a vital cog in Henri Michel's machine this summer. Sol Campbell(ENG, Arsenal)
If his club had lifted the trophy with the big ears, then Sol Campbell would surely have been elevated to the rank of hero. His imperious header may have given the English team the advantage, but in the end, he was repeatedly found wanting as Barcelona proceeded to wrest control of the encounter from their oppo
A．Y
B．N
C．NG
第5题
Senate Majority Leader Harry Reid: "Like any negotiation, this involved give and take, and if you don't mind my saying so that is an understatement."
The agreement drops the total to $789 billion, while both Senate and House-passed measures exceeded $800 billion.
A combination of low and middle income tax cuts, making up about 35 percent of the bill, and domestic spending, its supporters say it meets President Barack Obama's goal of creating or saving as many as 4 million jobs.
Susan Collins of Maine was among only 3 moderate Senate Republicans who joined the Democratic majority there. She says money trimmed from the bill reflects an effort to focus it more sharply to help the economy.
"It is a fiscally-responsible number that reflects our efforts to truly focus this bill on programs, and policies and tax relief that will help turn our economy around, create jobs and provide relief to the families of our country," she said.
Collins said the agreement increases spending on infrastructure projects, more than $150 billion in the proposed measure.
Republican opponents kept up their criticisms, primarily that the measure contains untargeted spending and not the right level of tax relief.
House Republican leader John Boehner voiced disappointment with the agreement, repeating his assertion that the measure will not create jobs quickly enough.
"It appears that they have made a bad bill worse by reducing the amount of tax relief for American families and small businesses, and adding more wasteful Washington spending," he said.
But Senator Arlen Specter, another moderate Republican who worked with Democrats, said action was required.
"This is obviously a very difficult vote in view of the large deficit and national debt which we have, but I believe it is indispensable, that strong action be taken," he said.
White House aides, including Chief of Staff Rahm Emanuel, joined in the negotiations on Capitol Hill.
Lawmakers behind the agreement hope a final conference report will be ready in the next 2 clays that the House and Senate will vote on. Approval would send the legislation to President Obama for signature.
An eventual Senate vote is expected to mirror earlier results in which majority Democrats, with help from the 3 Republicans, achieved the 60 votes needed to overcome any procedural block.
It remains to be seen how a vote will turn out in the House, where no Republicans supported a House-passed measure, but where Democrats hold a strong enough majority to pass measures easily.
House Republican leaders declined to predict Wednesday how many in their party might support final legislation.
"The agreement" (Line 2, Para. 1) is most probably a bill about ______.
A．stimulus for the economy
B．reform. of the legal system
C．funding for the educational system
D．expenditure on the national defence
第6题
听力原文： Sports can help you keep fit and get in touch with nature. However, whether you are on the mountains, in the waves, or on the grassland, you should be aware that your sport of choice might have great influence on the environment.
Some sports are resource-hungry. Golf, as you may know, eats up not only large areas of countryside, but also tons of water. Besides, all sorts of chemicals and huge amounts of energy are used to keep its courses in good condition. This causes major environmental effects. For example, in the dry regions of Portugal and Spain, golf is often held responsible for serious water shortage in some local areas.
There are many environment-friendly sports. Power walking is one of them that you could take up today. You don't need any special equipment except a good pair of shoes; and you don't have to worry about resources and your purse. Simple and free, power walking can also keep you fit. If you walk regularly, it will be good for your heart and bones. Experts say that 20 minutes of power walking daily can make you feel less anxious, sleep well and have better weight control.
Whatever sport you take up, you can make it greener by using environment-friendly equipment and buying products made from recycled materials. But the final goal should be "green gyms". They are better replacements for traditional health clubs and modern sports centers. Members of green gyms play sports outdoors, in the countryside or other open spaces. There is no special requirement for you to start your membership. And best of all, it's free.
Questions 29 to 32 are based on the passage you have just heard.
29. Which is the speaker most probably in favor of？
30. What do we know about golf from the passage？
31. Why does the speaker use power walking as an example？
32. What is the speaker's main purpose of giving this speech？
(33)
A．Cycling around a lake.
B．Motor racing in the desert.
C．Playing basketball in a gym.
D．Swimming in a sports center.
第7题
A.no one can be both creative and critical
B.they cannot be regarded as equally important
C.they are in constant conflict with each other
D.one cannot use them at the same time
第8题
That annual bicycle race, the Tour de France, much loved by the French is a good case in point. Just a few years back it was a strictly continental affair with France, Belgium and Holland, Spain and Italy taking part. But in recent years it has been dominated by Colombian mountain climbers, and American and Irish riders.
The people who really matter welcome the shift toward globalization. Peugeot, Michelin and Panasonic are multi-national corporations that want worldwide returns for the millions they invest in teams.' So it does them literally a world of good to see this unofficial world championship become just that.
This is undoubtedly an economic-based revolution we are witnessing here, one made possible by communications technology, but made to happen because of marketing considerations.
The skilfut way in which American football has been sold to Europe is a good example of how all sports will develop. The aim of course is not really to spread the sport for its own sake, but to increase the number of people interested in the major money-making events. The economics of the Superbowl are already astronomical. With seats at US $125, gate receipts alone were a staggering $10,000,000.
So it came as a terrible shock, but not really as a surprise, to learn that some people are now suggesting that soccer change from being a game of two 45-minute halves, to one of four 25-minute quarters. The idea is unashamedly to capture more advertising revenue, without giving any thought for the integrity of a sport which relies for its essence on the flowing nature of the action. Moreover, as sports expand into world markets, and as our choice of sports as consumers also grows, so we will demand to see them played at a higher and higher level.
Globalization of sporting culture means that ______.
A．more people are taking up sports
B．traditional sports are getting popular
C．many local sports are becoming international
D．foreigners are more interested in local sports
第9题
A．Y
B．N
C．NG
第10题
Which of the following is NOT true according to the passage？
A．Savill' s goal was of little help to the team of the Wimpole.
B．The game was'interrupted because of SavilI' s bizarre goal,
C．What Savill had done was quite rare among referees.
D．Savill didn' t want to be an example for other referees.
