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Who would have believed it After what seems like an eternity of tantalizing hype about "high-definition" television, the first digital sets are actually on their way to the market. This much anticipated debut would seem to be terrific news for tube lovers. As promised, the sets deliver super-sharp digital pictures, wide-format movie-style screens and magnificent stereo surround sound. So should everybody rush out to buy one Well...maybe not. HDTV"s obvious advantages over conventional sets are offset by significant disadvantages. For openers, there"s the price tag. Sony"s small set, with a 34-in screen, lists for a fairly large $8,999. Prices will eventually drop, of course, but Bill Mannion, general manager of Panasonic"s TV division, acknowledges, "It"s going to be a while, maybe years before most consumers can afford HDTV." Even if you"re a gadget freak with deep pockets, you may think twice about buying for another reason: "high definition" will not be equally high. Some programs will be broadcast at 480 lines of resolution (compared with 330 or so on conventional televisions), others at a sharper 720 lines, and still others at the maximum of 1,080. NBC says it plans to start by offering 480-line quality for day-time programming and 1,080 for some prime-time shows and specials. But cable-TV customers—a full two-thirds of American households—may get a sinking feeling of another sort if they try to tune in. Cable companies are refusing, for now, to carry broadcasters" HDTV signals, saying information-rich HDTV channels overtax their systems. Therefore viewers, who want decent reception, will have to buy clumsy, old-fashioned TV antennas if they plan to pull in digital broadcasts. One decision consumers won"t have to make is whether to buy a set that uses one format or another. Back in the days when VCRs were new, you could buy a VHS or a Beta-format machine; neither could read or record on the other"s tapes. Those who chose Beta generally regretted it, as VHS took over the market, video companies stopped releasing Beta-format movies, and Beta sets became essentially useless. Most reassuring of all, the new sets will be able to pick up conventional TV broadcasts. You won"t need two TV sets sitting side by side. Will that be enough to talk consumers into putting down the better part of $10,0007 Manufactures hope that wide-eyed excitement over this genuinely revolutionary new technology will help hide the fact that it"s still a work in progress. Realistically, they expect the revolution to be a slow one. According to the text, HDTV

A. has its limitations.
B. is a landmark in TV technology.
C. is likely to be accepted by the mass.
D. is doubted by manufacturers on its practicability.

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With the rapid spread of the internet eye where in the world, and the (1)_____ number of users, one of the most exciting developments on the internet is E-commerce—(2)_____ commerce. E-commerce has two forms, (3)_____ business-to-business, or B-to-B, and business-to-consumer, or B-to-C. B-to-C was the first of these developments. It grew (4)_____ from the first days when people started to buy things from their homes without going to a shop. First came "catalogue shopping" (5)_____ you choose what you want from a catalogue (6)_____ pictures and other details of everything that is (7)_____ sale. You then send an order with a check by (8)_____ and the things you have chosen sent to your home. Then (9)_____ "television shopping", where (10)_____ a catalogue, the items for sale are shown or (11)_____ on television to attract the customer. (12)_____, the customer sends a check and the item is delivered to his or her home. B-to-C is the (13)_____ development, where the "catalogue" is (14)_____ on the internet, combining the advantages of both the book catalogue and the television and indeed adding more (15)_____ The customer makes his choice but rather than sending an order and a (16)_____ through the post, he places the order and pays for it using his credit card, all using the (17)_____ Many people worry about giving (18)_____ of their credit card over the internet and the danger that it may be deceitfully used. (19)_____, the general view is that with modern systems of secure measures the dangers of the misuse of credit cards is (20)_____ greater in a shop, garage or restaurant than in using it for shopping on the internet.

A. directly
B. naturally
C. generally
D. specially

In a large, air-conditioned room in a conference center located in a city of more than a million people, well-qualified doctors of science discuss the pros and cons of global warming, and debate how the temperature of the sea is being measured. After several hours of discussion, they walk out into the warm sunshine of a summer"s day, heading off to a comfortable restaurant for lunch. On the same day, on the sands of small islands in the middle of the Pacific Ocean, baked hard by the burning sun, Hemi and Naqono look at the water lapping over the place where they once stored their potato plants. They watch the waves dashing gently at the feet of their straw huts which some years ago were many metres from the seashore. Global warming is a problem for theoretical discussion among scientists all over the world. For many Pacific Islanders it is now becoming a practical problem. While international science argues about global warming and climate change, low-lying Pacific Islands are already suffering coastal erosion and crop failures. In places such as Marshall Islands, where much of the land is only a metre above sea-level, villagers face leaving their slowly disappearing homes. Scientists and officials from 13 Pacific Island Countries discussed their concerns in a Pacific conference in Aukland, New Zealand, and examined a New Zealand computer model on climate change that could provide a valuable planning tool. Lack of meteorological and tidal research means Government agencies throughout the Pacific and the world have to rely largely on anecdotal of rising sea levels eroding foreshores, and increasingly severe droughts affecting the vital coconut crop. Australian research commissioned by the South Pacific Regional Environment Programme has already calculated that human greenhouse gas emissions already measured up to 1995 will cause a 5cm to 12cm sea-level rise by 2025. Pacific Island countries fear their vulnerable low-lying homes will be the first to pay the price for the emissions of industrialized nations. A Pacific Islands Climate Change Assistance Programme is already in place and is working on plans to help Pacific Islanders who have few resources to combat the fast-changing environmental circumstances. Yumi Crisostomo, of the Marshall Islands Environmental Protection Authority, said residents of some of the 1,225 islands in the group had reported alarming coastal erosion, forcing them to shift homes inland. Some islands were only about a kilometer across, so residents had little room to move. "We may have to look at the option of internal migration within the island group," he said. The first two paragraphs suggest that

A. global warming is not only a theoretical problem but also a practical one.
B. there is a great difference between the rich and poor.
C. science discussion has nothing to do with the practical problem.
D. well-qualified doctors know little about the reality of the problem.

Suppose you want to apply for admission to Washington University, but you can"t get all your materials ready before the stated deadline. Write a letter with your application materials to Washington University to 1) explain, and 2) earn a chance for yourself. You should write about 100 words. Do not use your own name. Use "Li Ming" instead. Do not write your address.

______直方图,是由于数据收集不正常,可能有意识地去掉下限以下的数据,或是在检测过程中存在某种人为因素所造成。

A. 折齿形
B. 孤岛形
C. 双峰形
D. 绝壁形

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