单选题There are several advantages in making computers as small as one can. Sometimes weight is particularly important. A modern aircraft, for example, carries quite a load of electronic apparatus. If it is possible to make any of these smaller, and therefore lighter, the aircraft can carry a bigger pay-load. This kind of consideration applies to space satellites and to all kinds of computers that have to be carried about. But weight is not the only factor. The smaller the computer the faster it can work. The signals go to and fro at a very high but almost constant speed. So if one can scale down all dimensions to, let us say, one tenth, the average lengths of the current-paths will be reduced to one tenth. So, very roughly speaking, scaling down of all linear dimensions in the ratio of one to ten also gives a valuable bonus: the speed of operation is scaled up 10 times. Other techniques allow even further speed increases. This increase of operation is a real advantage. There are some application in which computers could be used which require very fast response times. Many of these are military, of course; but military applications also have applications in engineering sooner or later. For example, automatic blind landing of aircraft requires continuous computer calculations which result in control of the aircraft flight. The more immediate the responses are, the more stable that control can be. Another advantage is that less power is required to run the computer. In space vehicles and satellites this is an important matter; but even in a trial application we need not waste power. Sometimes a computer takes so much power that cooling systems which require still more power have to be installed to keep the computer from getting too hot, which would increase the risk of faults developing. So a computer which does not need to be cooled saves power on two counts. Another advantage is reliability. Mini-computers have been made possible by the development of integrated circuits. Instead of soldering bits of wire to join separate components such as resistors and capacitors sometimes in the most intricate networks, designers can now produce many connected circuits in one unit which involves no soldering and therefore no risk of broken joints at all.

单选题Menorca or Majorca? It is that time of the year again. The brochures are piling up in travel agents while newspapers and magazines bulge with advice about where to go. But the traditional packaged holiday, a British innovation that provided many timid natives with their first experience of warm sand, is not what it was. Indeed, the industry is anxiously awaiting a High Court ruling to find out exactly what it now is. Two things have changed the way Britons research and book their holidays: low-cost airlines and the Internet. Instead of buying a ready-made package consisting of a flight, hotel, car hire and assorted entertainment from a tour operator"s brochure, it is now easy to put together a trip using an online travel agent like Expedia or Travelocity, which last July bought Lastminute. com for ￡ 577 million ($1 billion), or from the proliferating websites of airlines, hotels and car-rental firms. This has led some to sound the death knell for high-street travel agents and tour operators. There have been upheavals and closures, but the traditional firms are starting to fight back, in part by moving more of their business online. First Choice Holidays, for instance, saw its pre-tax profit rise by 16% to ￡ 114 million ($195 million) in the year to the end of October. Although the overall number of holidays booked has fallen, the company is concentrating on more valuable long-haul and adventure trips. First Choice now sells more than half its trips directly, either via the Internet, over the telephone or from its own travel shops. It wants that to reach 75% within a few years. Other tour operators are showing similar hustle. MyTravel managed to cut its loss by almost half in 2005. Thomas Cook and Thomson Holidays, now both German owned, are also bullish about the coming holiday season. Highstreet travel agents are having a tougher time, though, not least because many leading tour operations have cut the commissions they pay. Some high-street travel agents are also learning to live with the Internet, helping people book complicated trips that they have researched online, providing advice and tacking on other services. This is seen as a growth area. But if an agent puts together separate flights and hotel accommodation, is that a package, too? The Civil Aviation Authority (CAA) says it is and the agent should hold an Air Travel Organisers Licence, which provides financial guarantees to repatriate people and provide refunds. The scheme dates from the early 1970s, when some large British travel firms went bust, stranding customers on the Costas. Although such failures are less common these days, the CAA had to help out some 30,000 people last year. The Association of British Travel Agents went to the High Court in November to argue such bookings are not traditional packages and so do not require agents to acquire the costly licences. While the court decides, millions of Britons will happily click away buying online holidays, unaware of the difference.

单选题You might guess that experienced drivers have fewer accidents, but research from insurer AXA has revealed that they are more law-abiding and honest, too. A poll of 2 000 drivers in the UK found that those who have been behind the wheel for eight years or more had not only caused half as many accidents in the last year as less experienced drivers, but were also less likely to have broken the law or lied to their insurer. Experienced drivers were half as likely to have been caught using a mobile phone while driving within the last year; and a third as likely to have been caught driving under the influence of alcohol or drugs, or to have been convicted of dangerous driving. They were also a fifth as likely to have been convicted of driving without a seatbelt. Dishonest behavior appears to be much more common among newer drivers. The UK's experienced drivers have always been an attractive group for insurers, but the much lower risk they present is rarely fully reflected in their premiums. This is why AXA has entered the direct car insurance market with a product that rewards them with a no-claims discount of up to 90 percent--far higher than anything else on the market. Only those drivers who have been claim-free for eight years or more will be eligible, which could offer large savings for around a third of motorists. AXA's research has enabled it to tailor not only the pricing to these expert drivers, but the service, too. AXA Car Insurance will offer a courtesy ear whenever yours is out of action due to accident, fire or theft, not just while it's being repaired. The survey found they wanted higher service levels too, so customers will be able to change their policy details online or track a claim at any hour of the day or night, every day of the year. Many drivers wrongly assumed they were insured if they were injured in accidents that are their faults. To plug the gap, AXA has introduced Driver Injury Cover,which pays up to ￡1 million for medical treatment and loss of earnings for an additional annual premium of ￡34.99--less than ￡3 a month. Cocky newer drivers do appear to be somewhat overconfident. A third of those who'd been on the road for between only one and two years claimed they were already experienced drivers, and that rose to a half among those who'd been driving for just one more year. But, as AXA's survey demonstrates, they have still got a lot to learn., they will need to be driving for at least five more years before they can take advantage of that 90 per cent no-claims discount.

单选题In the eyes of the writer, the current insurance industry alone ______.

单选题{{B}}Text 4{{/B}} Mark Twain once observed that giving up smoking is easy. He knew, because he' d done it hundreds of times himself. Giving up for ever is a trifle more difficult, apparently, and it is well known that it is much more difficult for some people than for others. Why is this so? Few doctors believe any longer that it is simply a question of will power. And for those people that continue to view addicts as merely "weak", recent genetic research may force a rethink. A study conducted by Jacqueline Vink, of the Free University of Amsterdam, used a database called the Netherlands Twin Register to analyze the smoking habits of twins. Her results, published in the Pharmacogenomics Journal, suggest that an individual' s degree of nicotine dependence, and even the number of cigarettes he smokes per day, are strongly genetically influenced. The Netherlands Twin Register is a voluntary database that contains details of some 7,000 pairs of adult twins (aged between 15 and 70) and 28,000 pairs of childhood twins. Such databases are prized by geneticists because they allow the comparison of identical twins (who share all their genes) with fraternal twins (who share half). In this case, however, Dr. Vink did not make use of that fact. For her, the database was merely a convenient repository of information. Instead of comparing identical and fraternal twins, she concentrated on the adult fraternal twins, most of whom had completed questionnaires about their habits, including smoking, and 536 of whom had given DNA samples to the register. The human genome is huge. It consists of billions of DNA "letters", some of which can be strung together to make sense ( the genes) but many of which have either no function, or an unknown function, To follow what is going on, geneticists rely on markers they have identified within the genome. These are places where the genetic letters may vary between individuals. If a particular variant is routinely associated with a particular physical feature or a behavior pattern, it suggests that a particular version of a nearby gene is influencing that feature or behavior. Dr. Vink found four markers which seemed to be associated with smoking. They were on chromosomes 3, 6, 10 and 14, suggesting that at least four genes are involved. Dr. Vink hopes that finding genes responsible for nicotine dependence will make it possible to identify the causes of such dependence. That will help to classify smokers better (some are social smokers while others are physically addicted) and thus enable "quitting" programs to be customized. Results such as Dr. Vink' s must be interpreted with care. Association studies, as such projects are known, have a disturbing habit of disappearing, as it were, in a puff of smoke when someone tries to replicate them. But if Dr. Vink really has exposed a genetic link with addiction, then Mark Twain' s problem may eventually become a thing of the past. Mark Twain once observed that giving up smoking is easy. He knew, because he' d done it hundreds of times himself. Giving up for ever is a trifle more difficult, apparently, and it is well known that it is much more difficult for some people than for others. Why is this so? Few doctors believe any longer that it is simply a question of will power. And for those people that continue to view addicts as merely "weak", recent genetic research may force a rethink. A study conducted by Jacqueline Vink, of the Free University of Amsterdam, used a database called the Netherlands Twin Register to analyze the smoking habits of twins. Her results, published in the Pharmacogenomics Journal, suggest that an individual' s degree of nicotine dependence, and even the number of cigarettes he smokes per day, are strongly genetically influenced. The Netherlands Twin Register is a voluntary database that contains details of some 7,000 pairs of adult twins (aged between 15 and 70) and 28,000 pairs of childhood twins. Such databases are prized by geneticists because they allow the comparison of identical twins (who share all their genes) with fraternal twins (who share half). In this case, however, Dr. Vink did not make use of that fact. For her, the database was merely a convenient repository of information. Instead of comparing identical and fraternal twins, she concentrated on the adult fraternal twins, most of whom had completed questionnaires about their habits, including smoking, and 536 of whom had given DNA samples to the register. The human genome is huge. It consists of billions of DNA "letters", some of which can be strung together to make sense ( the genes) but many of which have either no function, or an unknown function, To follow what is going on, geneticists rely on markers they have identified within the genome. These are places where the genetic letters may vary between individuals. If a particular variant is routinely associated with a particular physical feature or a behavior pattern, it suggests that a particular version of a nearby gene is influencing that feature or behavior. Dr. Vink found four markers which seemed to be associated with smoking. They were on chromosomes 3, 6, 10 and 14, suggesting that at least four genes are involved. Dr. Vink hopes that finding genes responsible for nicotine dependence will make it possible to identify the causes of such dependence. That will help to classify smokers better (some are social smokers while others are physically addicted) and thus enable "quitting" programs to be customized. Results such as Dr. Vink' s must be interpreted with care. Association studies, as such projects are known, have a disturbing habit of disappearing, as it were, in a puff of smoke when someone tries to replicate them. But if Dr. Vink really has exposed a genetic link with addiction, then Mark Twain' s problem may eventually become a thing of the past. Mark Twain once observed that giving up smoking is easy. He knew, because he' d done it hundreds of times himself. Giving up for ever is a trifle more difficult, apparently, and it is well known that it is much more difficult for some people than for others. Why is this so? Few doctors believe any longer that it is simply a question of will power. And for those people that continue to view addicts as merely "weak", recent genetic research may force a rethink. A study conducted by Jacqueline Vink, of the Free University of Amsterdam, used a database called the Netherlands Twin Register to analyze the smoking habits of twins. Her results, published in the Pharmacogenomics Journal, suggest that an individual' s degree of nicotine dependence, and even the number of cigarettes he smokes per day, are strongly genetically influenced. The Netherlands Twin Register is a voluntary database that contains details of some 7,000 pairs of adult twins (aged between 15 and 70) and 28,000 pairs of childhood twins. Such databases are prized by geneticists because they allow the comparison of identical twins (who share all their genes) with fraternal twins (who share half). In this case, however, Dr. Vink did not make use of that fact. For her, the database was merely a convenient repository of information. Instead of comparing identical and fraternal twins, she concentrated on the adult fraternal twins, most of whom had completed questionnaires about their habits, including smoking, and 536 of whom had given DNA samples to the register. The human genome is huge. It consists of billions of DNA "letters", some of which can be strung together to make sense ( the genes) but many of which have either no function, or an unknown function, To follow what is going on, geneticists rely on markers they have identified within the genome. These are places where the genetic letters may vary between individuals. If a particular variant is routinely associated with a particular physical feature or a behavior pattern, it suggests that a particular version of a nearby gene is influencing that feature or behavior. Dr. Vink found four markers which seemed to be associated with smoking. They were on chromosomes 3, 6, 10 and 14, suggesting that at least four genes are involved. Dr. Vink hopes that finding genes responsible for nicotine dependence will make it possible to identify the causes of such dependence. That will help to classify smokers better (some are social smokers while others are physically addicted) and thus enable "quitting" programs to be customized. Results such as Dr. Vink' s must be interpreted with care. Association studies, as such projects are known, have a disturbing habit of disappearing, as it were, in a puff of smoke when someone tries to replicate them. But if Dr. Vink really has exposed a genetic link with addiction, then Mark Twain' s problem may eventually become a thing of the past.

单选题The first paragraph mainly tells us that

单选题According to the passage, it is possible that e-paper

单选题By mentioning "the figures are as changeable as a mirage in the desert", the author is talking about ______.

单选题For the patients the author describes that

单选题In the author's opinion, this kind of bill

单选题{{B}}Text 2{{/B}} Whether to teach young children a second language is disputed among teachers, researchers and pushy parents. On the one hand, acquiring a new tongue is said to be far easier when young. On the other, teachers complain that children whose parents speak a language at home that is different from the one used in the classroom sometimes struggle in their lessons and are slower to reach linguistic milestones. Would a 15-month-old child, they wonder, not be better off going to music classes? A study just published in the Proceedings of the National Academy of Sciences may help resolve this question by getting to the point of what is going on in a bilingual child’s brain, how a second language affects the way he thinks, and thus in what circumstances being bilingual may be helpful. Agnes Kovacs and Jacques Mehler at the International School for Advanced Studies in Trieste say that some aspects of the cognitive development of infants raised in a bilingual household must be undergoing acceleration in order to manage which of the two languages they are dealing with. The aspect of cognition in question is part of what is termed the brain’s “executive function”. This allows people to organise, plan, prioritise activity, shift their attention from one thing to another and suppress habitual responses. Bilingualism is common in Trieste which, though Italian, is almost surrounded by Slovenia. So Dr. Kovacs and Dr. Mehler looked at 40 “preverbal” seven-month-olds, half raised in monolingual and half in bilingual households, and compared their performances in a task that needs control of executive function. First, the babies were trained to expect the appearance of a puppet on a screen after they had heard a set of meaningless words invented by the researchers. Then the words, and the location of the puppet, were changed. When this was done, the babies who speak only one language had difficulty overcoming their learnt response, even when the researchers gave them further clues that a switch had taken place. The bilingual babies, however, found it far easier to switch their attention — counteracting the previously learnt, but no longer useful response. Monitoring languages and .keeping them separate is part of the brain’s executive function, so these findings suggest that even before a child can speak, a bilingual environment may speed up that function’s development. Before rushing your offspring into bilingual kindergartens, though, there are a few cautions. For one thing, these extraordinary cognitive benefits have been demonstrated so far only in “crib” bilinguals — those living in households where two languages are spoken routinely. The researchers speculate that it might be the fact of having to learn two languages in the same setting that requires greater use of executive function. So whether those benefits apply to children who learn one language at home, and one at school, remains unclear.

单选题It can be concluded that during an anti-El Nifio the faster-moving signal waves are