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Dreams of FlightThe story of man’s dream of flight, of his desire to reach the stars, is as old as mankind itself. According to Greek legend, Daedalus was the first man to fly. He and his son had been kept on an island, in order to escape, Daedalus shaped wings of wax (蜡) into which he stuck bird feathers. During their flight, his son flew too high and the sun melted the wax. He was drowned in the sea. The father was supposed to have continued his Night and reached Sicily, several hundred miles away.There is also an English legend of King Bladud who, during his rule in the ninth century B.C., used wings to fly. But his flight was short-lived and he fell to his death. The dream of flying continued, but in all the legends, the flier rose like a bird only to fall like a stone. It took hundreds of years that men flew up into the air and returned to earth safely.The first man to approach flying on a scientific basis was an Englishman who lived during the thirteenth century. He looked at the air about us as a sea, and he believed that a balloon could float on the air just as a boat did on water. Almost four hundred years later, an Italian priest applied his principle of air flight. He designed a boat, which would be held in the air by four hollow spheres (空心球). Each of the four balls was to be 20 feet in diameter (直径) and made of very thin copper. But his boat was never .built since it was not possible to make spheres of such thin metal and such size in those days.After studying the flight of birds and the movement of the air, a great scientist of the fifteenth century concluded that birds flew because they flapped (摆动) their wings and that it was possible for man to do the same. So a kind of flapping-wing flying machine was invented. Many men tried and failed to fly with flying machines. It was not until 1890 that people discovered why this method would never succeed-man could not develop sufficient power with his arms and legs. The priest failed to build the boat because()
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Questions 11 to 18 are based on the conversation you have just heard.
Science and Truth"FINAGLE" is not a word that most people associate with science. One reason is that the image of the scientist is of one who always collects data in an impartial (51) for truth. In any debate - over intelligence, schooling, energy-the (51) "science says" usually disarms opposition.But scientists have long acknowledged the existence of a "finagle factor"—a tendency by many scientists to give a helpful change to the data to (53) desired results. The latest of the finagle factor in action comes from Stephen Jay Gould, a Harvard biologist, (54) has examined the important 19th century work of Dr. Samuel George Morton. Morton was famous in his time (55) analysing the brain size of the skulls as a measure of intelligence. He concluded that whites had the (56) brains, that the brains of Indians and Blacks were smaller, and therefore, that whites constitute a superior race.Gould went back to Morton’s original data and concluded that the (57) were an example of the finagle at work. He found that Morton’s "discovery" was made by leaving out embarrassing data, using incorrect procedures, making simple arithmetical (58) (always in his favour) and changing his criteria-again, always in favour of his argument. Morton has been thoroughly discredited by now and scientists do not believe that brain size reflects (59) .But Gould went on to say Morton’s story is only an example of a common problem in (60) work. Some of the leading figures in science are believed to have (61) the finagle factor. Gould says that Isaac Newton fudged out to support at least three central statements that he could not prove. And so (62) Claudius Ptolemy, the Greek astronomer, whose master work, Almagest, summed up the case for a solar system that had the earth as its centre. Recent studies indicate that Ptolemy (63) faked some key data or resorted heavily to the finagle factor.All this is (64) because the finagle factor is still at work. For example, in the artificial sweetener controversy, for example, it is said that all the studies sponsored by the sugar industry find that the artificial sweetener is unsafe, while all the studies sponsored by the diet food industry find nothing (65) with it. 63（）
Questions 11 to 18 are based on the conversation you have just heard.
It’s in the CardsIn recent years, more and more people have been paying for things with credit cards. There are now 565 million credit cards worldwide, but it doesn’t stop there. Debit cards (电子记账卡) are being issued by banks, and store cards are being offered by many department stores. Bills and coins are gradually being replaced by "plastic money." In many countries, phone cards have been introduced for people to use in pay phones. In addition, cards made of paper are being replaced by plastic ones by many organizations and clubs. For example, if you belong to a sports club, your membership card may well be made of plastic.How safe is the plastic used to make these cards, though Until now, most cards have been made from a plastic called PVC. While PVC is being produced, harmful chemicals are released into the atmosphere. One of the most dangerous chemicals that is released is dioxin, which is known to cause cancer in humans. A further problem is that, when a PVC card is thrown away, it is not biodegradable; this means that it does not "break down" and cannot be recycled. Obviously, recycling reduces pollution of the environment.The executive director of the environmental organization and charity Greenpeace, Peter Melchett, says, "If there is a solution to this-and an alternative then it would be madness not to use it." Greenpeace has found a solution and an alternative. Their new credit card is made entirely from a biodegradable plastic that uses plants. The card breaks down in around three months in soil; in this way, it is recycled. In contrast, a PVC card lasts for centuries. Greenpeace hopes that many organizations will soon follow their example and issue cards that do not threaten the public health. The cards that are wildly used now are credit.cards.()
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