单选题The tone of the text can best described as______.

单选题Patrick Moorer seemed to believe that putting men on Mars within the next few decades was ______.

单选题As Philadelphia grew from a small town into a city in the first half of the eighteenth century, it became an increasingly important marketing center for a vast agricultural hinterland. Market days (1) the crowded city even more crowded, as farmers from within a (2) of 24 or more kilometers brought their sheep, vegetables, cider and other products for direct sale to the (3) . The High Street Market was continuously (4) throughout the period until 1736, (5) it (6) from Front Street to Third. By 1745 New Market was opened on Second Street. The next year the Callow Hill Market began (7) . Along with market days, the (8) of twice-yearly fairs persisted in Philadelphia (9) after similar trading days had been discontinued in other colonial cities. The (10) provided a means of bringing handmade goods from (11) places to would-be buyers in the city. Linens and stockings from Germantown, (12) , were popular items. Auctions were another popular (13) of trade. Because of the competition, retail (14) opposed these as well as the fairs. (15) governmental attempts to eradicate fairs and auctions were less than successful, the ordinary (16) of economic development was on the merchants'side, as increasing business specialization became the (17) of the day. Export merchants became differentiated from their importing counterparts, and specialty shops began to appear (18) general stores selling a variety of goods. One of the reasons Philadelphia's merchants prospered was because the surrounding area was undergoing tremendous economic and demographic growth. They did their business, (19) , in the capital city of the province, (20) to not only the governor and his circle, but citizens from all over the colony.

单选题The author does not include among the sciences the study of

单选题When the author says "there will be no escaping Pottermania", he implies that______.

单选题Multifunction superpills aren't nearly as farfetched as they may sound. And reducing such serious risks to heart health as soaring cholesterol, diabetes, and high blood pressure potentially could save many lives and be highly lucrative for drug companies. A combo pill from Pfizer (PFE) of its hypertension drug Norvasc and cholesterol-lowering agent Lipitor "could have huge potential," says Shaojing Tong, analyst at Mehta Partners. "Offering two functions in one pill itself is a huge convenience." If such pills catch on, they could generate significant revenues for drug companies. In Pfizer's ease, the goal is to transfer as many qualified patients as possible to the combo pill. Norvasc's patents expire in 2007, but Pfizer could avoid losing all its revenues from the drug at once if it were part of a superpill. Sena Lund, an analyst at Cathay Financial, sees Pfizer selling $4.2 billion worth of Norvasc-Lipitor by 2007. That would help take up the slack for falling sales of Lipitor, which he projects will drop to $5 billion in 2007, down from $ 8 billion last year. Pfizer argues that addressing two distinct and serious cardiovascular risk factors in one pill has advantages. People with both hypertension and high LDL cholesterol (the "bad" kind) number around 27 million in the U. S. , notes Craig Hopkinson, medical director for dual therapy at Pfizer, and only 2% of that population reaches adequate treatment goals. Taking two treatments in one will increase the number of patients who take the medications properly and "assist in getting patients to goal," be says. Doctors also may be quick to adopt Norvasc-Lipitor, Pfizer figures, because it's made up of two well-studied drugs, which many physicians are already familiar with. But Dr. Stanley Rockson, chief of consultative cardiology at Stanford University Medical Center, says fixed-dose combination pills represent "an interesting crossroads" for physicians, who are typically trained to "approach each individual problem with care." Combining treatments would challenge doctors to approach heart disease differently. But better patient compliance is important enough, says Rockson, that he expects doctors, to Be open to trying the combined pill. Some other physicians are more skeptical. "If you want to change dosage on one of the new pill's two drugs, you're stuck," fears Dr. Irene Gavris, professor of medicine at Boston University School of Medicine. She says she would feel most comfortable trying the combination pill on patients who "have been on the drugs for a while" and are thus unlikely to need changes in dosage. As usual, economics could tip the scales. Patients now taking both Lipitor and Norvasc "could cut their insurance co pay in half" by switching to the combo drug, Gavris notes. That's a key advantage. Controlling hypertension, for instance, can require three or more drugs, and the financial burden on patients mounts quickly. If patients also benefit--as Pfizer and other drug companies contend--making the switch to superpills could be advantageous for everyone.

单选题{{B}}Text 2{{/B}} 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 Culture shock might be called an occupational disease of people who have been suddenly transplanted abroad. Like most ailments, it has its own{{U}} {{U}} 1 {{/U}} {{/U}}and cure. Culture shock is{{U}} {{U}} 2 {{/U}} {{/U}}by the anxiety that results from losing all our familiar signs and symbols of social intercourse. Those signs or cues include the thousand and one{{U}} {{U}} 3 {{/U}} {{/U}}in which we orient ourselves to the{{U}} {{U}} 4 {{/U}} {{/U}}of daily life: when to shake hands and what to say when we meet people, when and how to give tips, how to{{U}} {{U}} 5 {{/U}} {{/U}}purchases, when to accept and when to refuse invitations, when to take statement seriously and when not. These cues,{{U}} {{U}} 6 {{/U}} {{/U}}may be words, gestures, facial{{U}} {{U}} 7 {{/U}} {{/U}}customs, or norms, are{{U}} {{U}} 8 {{/U}} {{/U}}by all of us in the course of growing up and are as much a{{U}} {{U}} 9 {{/U}} {{/U}}of our culture as the language we speak or the beliefs we accept. All of us{{U}} {{U}} 10 {{/U}} {{/U}}for our peace of mind and our efficiency on hundreds of these cues,{{U}} {{U}} 11 {{/U}} {{/U}}of which we do not carry on the{{U}} {{U}} 12 {{/U}} {{/U}}of conscious awareness. Now when an individual{{U}} {{U}} 13 {{/U}} {{/U}}a strange culture, all or most of these familiar cues are removed. He or she is like a fish out of water. No matter how broad-minded or{{U}} {{U}} 14 {{/U}} {{/U}}of goodwill you may be, a series of props have been{{U}} {{U}} 15 {{/U}} {{/U}}under you, followed by a feeling of frustration and{{U}} {{U}} 16 {{/U}} {{/U}}. People react to the frustration in much the{{U}} {{U}} 17 {{/U}} {{/U}}way. First they reject the environment which causes the{{U}} {{U}} 18 {{/U}} {{/U}}. "The ways of the host country are bad because they make us feel bad." When foreigners in a strange land get together to{{U}} {{U}} 19 {{/U}} {{/U}}about the host country and its people, you can be sure they are{{U}} {{U}} 20 {{/U}} {{/U}}from culture shock.

单选题{{B}}Text 4{{/B}} Timothy Berners-Lee, might be giving Bill Gates a run for the money, but he passed up his shot at fabulous wealth -- intentionally--in 1990. That's when he decided not to patent the technology used to create the most important software innovation in the final decade of the 20th century: the World Wide Web. Berners-Lee wanted to make the world a richer place, not amass personal wealth. So he gave his brainchild to us all. Berners-Lee regards today's Web as a rebellious adolescent that can never fulfill his original expectations. By 2005, he hopes to begin replacing it with the Semantic Web--a smart network that will finally understand human languages and make computers virtually as easy to work with as other humans. As envisioned by Berners-Lee, the new Web would understand not only the meaning of words and concepts but also theological relationships among them. That has awesome potential. Most knowledge is built on two pillars: semantic and mathematics. In number-crunching, computers already outclass people. Machines that are equally admit at dealing with language and reason won't just help people uncover new insights; they could blaze new trails on their own. Even with a fairly crude version of this future Web, mining online repositories for nuggets of knowledge would no longer force people to wade through screen after screen of extraneous data. Instead, computers would dispatch intelligent agents, or software messengers, to explore Websites by the thousands and logically sift out just what's relevant. That alone would provide a major boost in productivity at work and at home. But there's far more. Software agents could also take on many routine business chores, such as helping manufacturers find and negotiate with lowest-cost parts suppliers and handling help-desk questions. The Semantic Web would also be a bottomless trove of eureka insights. Most inventions and scientific breakthronghs, including today's Web, spring from novel combinations of existing knowledge. The Semantic Web would make it possible to evaluate more combinations overnight than a person could juggle in a lifetime. Sure scientists and other people can post ideas on the Web today for others to read. But with machines doing the reading and translating technical terms, related ideas from millions of Web pages could be distilled and summarized. That will lift the ability to assess and integrate information to new heights. The Semantic Web, Berners-Lee predicts, "will help more people become more intuitive as well as more analytical. It will foster global collaborations among people with diverse cultural perspectives, so we have a better chance of finding the right solutions to the really big issues--like the environment and climate warming."

单选题Current Group, a Germantown-based technology firm, has taken over an ordinary looking house in Bethesda and turned it into a laboratory for smart-grid technology, the system the company believes will bring the nation"s electricity grids into the digital age. In the front yard stands a utility pole hooked up to a special transformer that connects the power lines to high-speed Intemet. Hundreds of sensors attached to the lines monitor how power flows through the home. That information is then sent back to the utility company. The process lets a utility more efficiently manage the distribution of electricity by allowing two-way communication between consumers and energy suppliers via the broadband network on the power lines. Based on data they receive from hundreds of homes, utilities can monitor usage and adjust output and pricing in response to demand. Consumers can be rewarded with reduced rates by cutting back on consumption during peak periods. And computerized substations can talk to each other so overloaded circuits hand off electricity to those that have not fully loaded, helping to prevent blackouts. Some utility companies have launched initiatives to give consumers data about their energy consumption habits in an effort to lower energy bills. Smart-grid technology takes such programs further by automating electricity distribution, which would make grids more reliable and efficient. By partnering with utilities, the company hopes to tap into $4.5 billion in stimulus grants intended to encourage smart-grid development. When he announced the funding, President Obama pointed to a project in Boulder, Colo., as an example of a successful smart-grid experiment. Current is one of the companies working on the project. Current"s chief executive Tom Casey believes the technology will help utility companies better distribute electricity produced by renewable resources, such as solar panels or wind farms. "A smart grid"s system can be paired up with the renewable resources so that when the renewable source is varying, the overall load can be varied as well," Casey told the House Select Committee on Energy Independence and Global Warming. "This will reduce or eliminate the need for backup coal or gas-based power generation plants."