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第(38)～(40) 题基于学生一课程数据库中的3个基本表： 学生信息表：s(sno，sname，sex，age，dept)主码为sno 课程信息表：c(cno，cname，teacher)主码为cno 学生选课信息表：sc(sno，cno，grade)主码为(sno，cno) 在“查询选修课程号为2，且成绩在70分以上的所有学生的学号、姓名和选课名称”的 SQL语句中，将使用到的表是
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案例分析题Insurance companies provide a service to the community by protecting it against expected and unexpected disasters. Before an insurance company will agree to (1) anything, it collects accurate figures about the (2) . It knows, for example, that the risk of a man being killed in a plane accident is less than the risk he (3) in crossing a busy road. This (4) it to quote low figures for travel insurance. Sometimes the risk may be high, as in motorracing or mountaineering. Then the company (5) a much higher price. (6) too many climbers have accidents, the price rises still further. If the majority of climbers fall off mountains, the company will (7) to insure them.An ordinary householder may wish to protect his home against fire or his (8) against burglary. A shop keeper may wish to insure against (9) . In (10) cases, the company will check its statistics and quote a premium. If it is (11) , it may refuse to quote. If it insures a shop and then receives a suspicious (12) , it will (13) the claim as a means of protecting itself against false claims. It is not unknown for a businessman in debt to burn down his own premises so that he can claim much money from his insurance company. He can be sure that the fire will be investigated most carefully. Insurance companies also (14) insurance against shipwreck or disaster in the air. Planes and ships are very expensive, so a large (15) is charged, but a (16) is given to companies with an accident-free record.Every week insurance companies receive premium (17) from customers. These payments can form a very large total (18) millions of dollars. The company does not leave the money in the bank. It (19) in property, shares, farms and even antique paintings and stamps. Its aim is to obtain the best possible return on its investment. This is not so greedy as it may seem, since this is one way by which it can deep its premiums down and continue to make a profit (20) being of service to the community. 3（）
案例分析题Invention and innovation have been quintessentially American pursuits from the earliest days of the republic. Benjamin Franklin was a world-famous scientist and inventor. Cyrus McCormick and his harvester, Samuel F. B. Morse and the telegraph, Alexander Graham Bell and the telephone—the 19th century produced a string of inventors and their world-changing creations. And then there was the greatest of them all, Thomas Alva Edison. He came up with the crucial devices that would give birth to three enduring American industries:electrical power, recorded music and motion pictures. Much of the world we live in today is a legacy of Edison and of his devotion to science and innovation. Edison taught us to invent, and for decades we were the best in the world. But today, more than 160 years after Edison’s birth, America is losing its scientific edge. A landmark report released in May by the National Science Board lays out the numbers:while U. S. investment in R&D as a share of total GDP has remained relatively constant since the mid-1980s at 2.7% , the federal share of R&D has been consistently declining—even as Asian nations like Japan and South Korea have rapidly increased that ratio. At the same time, American students seem to be losing interest in science. Only about one-third of U. S. bachelor’s degrees are in science or engineering now, compared with 63% in Japan and 53% in China. It’s ironic that nowhere is America’s position in science and technology more threatened than in the industry that Edison essentially invented: energy. Clean power could be to the 21st century what aeronautics and the computer were to the 20th, but the U. S. is already falling behind. Meanwhile, Congress remains largely paralyzed. Though in May the House of Representatives was finally able to pass the $ 86 billion America Competes Reauthorization Act, which would double the budgets of the National Science Foundation (NSF) and Energy Department’s Office of Science, the bill’s fate is cloudy in the deadlocked Senate. "At this rate... we’ll be buying most of our wind generators and photovoltaic panels from other countries, " former NSF head Arden L. Bement said at a congressional hearing recently. "That’s what keeps me awake sometimes at night. " Some erosion of the U. S. ’s scientific dominance is inevitable in a globalized world and might not even be a bad thing. Tomorrow’s innovators could arise in Shanghai or Seoul or Bangalore. And Edison would counsel against panic—as he put it once, " Whatever setbacks America has encountered, it has always emerged as a stronger and more prosperous nation. " But the U. S. will inevitably decline unless we invest in the education and research necessary to maintain the American edge. The next generation of Edisons could be waiting. But unless we move quickly, they won’t have the tools they need to thrive. According to paragraph 2, which of the following decreasessince the mid-1980s（）
案例分析题The first time I tried shark-fin soup was at Time Warner’s annual dinner in Hong Kong. Shark-fin soup is a luxury item ($100 bowl in some restaurants)in Hong Kong and Mainland China, its biggest consumers; it’s a dish that embodies east Asia’s intertwined notions of hospitality and keeping (or losing) "face". "It’s like champagne", says Alvin Leung, owner of Bo Innovation, a Cantonese restaurant in Hong Kong. "You don’t open a bottle of Coke to celebrate. It’s a ritual. " Unfortunately, this gesture of hospitality comes with a price tag much bigger than that $ 100 bowl. All told, up to 70 million sharks are killed annually for the trade, despite the fact that 30% of shark species are threatened with extinction. "Sharks have made it through multiple mass extinctions on our planet, " says Matt Rand, director of Pew’s Global Shark Conservation division. "Now many species are going to go the way of the dinosaur—for a bowl of soup. " The shark-fin industry has gained notoriety in recent years not just because of what it’s doing to the global shark population but also because of what’s known as finning—the practice of catching a shark, removing its fins and dumping the animal back into the sea. While a pound of shark fin can go for up to $ 300, most shark meat isn’t particularly valuable, and it takes up freezer space and weight on fishing boats. Today, finning is illegal in the waters of the E. U. , the U. S. and Australia, among others; boats are required to carry a certain ratio of fins to carcasses(尸体) to prevent massive overfishing. But there are loopholes in antifinning laws that are easy to exploit. In the E. U. , for example, ships can land the fins separately from the carcasses, making the job of monitoring the weight ratio nearly impossible. In the U. S. , a boat found carrying nearly 65, 000 lb. ( 30, 000 kg) of illegal shark fins won a court case because it was registered as a cargo vessel, which current U. S. finning. laws do not cover. Sharks populations can’t withstand commercial fishing the way more fertile marine species can. Unlike other fish harvested from the wild, sharks grow slowly. They don’t reach sexual maturity until later in life—the female great white, for example, at 12 to 14 years—and when they do, they have comparatively few offspring at a time, unlike, tunas, which release millions of eggs when they spawn. The shark’s plight is starting to be weighed against the delicacy’s cultural value. The conservation group has lobbied local restaurants that offer the classic nine-course banquet served at Cantonese weddings, of which shark fin is traditionally a part, to offer a no-shark menu as a choice to couples. After my first encounter with shark-fin soup, I decided that, like my colleagues, I would probably skip it next time. Unfortunately, that next time came at an intimate dinner in a small, private dining room, where I was both a guest and a stranger. When the soup—the centerpiece of the meal—was set down before me, I ate it. Apparently, I’m not the only one to cave. "You go to a wedding, and you refused to eat it just because you feel you’re insulted— I’m not that extreme, " Leung, the chef, says. "If other people believe that it brings luck .or brings face, I’d be a spoilsport. "To make a dent in the slaughter of the sharks, however, there are going to have to be a lot of people willing to spoil this particular sport. It can be inferred from the passage that （）.
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