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Science develops through objective analysis, instead of through personal belief. Knowledge gained in science accumulates as time goes by, building on work performed earlier. Some of this knowledge-such as our understanding of numbers-stretches back’ to the time of ancient civilizations, when scientific thought first began. Other scientific knowledge such as our understanding of genes that cause cancer or of quarks (the smallest known building block of matter) -dates back less than 50 years. However, in all fields of science, old or new, researchers use the same systematic approach, known as the scientific method, to add to what is known.41__________. For example, in 1676, the English physicist Robert Hooke discovered that elastic objects, such as metal springs, stretch in proportion to the force that acts on them. Despite all the advances that have been made in physics since 1676, this simple law Still holds true.42__________. Sometimes scientific predictions go much further by describing objects or events that are not yet known. An outstanding instance occurred in 1869, when the Russian chemist Dmitry Mendeleyev drew up a periodic table of the elements arranged to illustrate patterns of recurring chemical and physical properties.43__________. At the time, most geologists discounted Wegener’s ideas, because the Earth’s crust seemed to be fixed. But following the discovery of plate tectonics in the 1960s, in which scientists found that the Earth’s crust is actually made of moving plates, continental drift became an important part of geology.Through advances like these, scientific knowledge is constantly added to and refined. As a result, science gives us an ever more detailed insight into the way the world around us works.44__________. However, with the dawn of the Industrial Revolution in the 18th century, this rapidly changed. Today, science has a profound effect on the way we live, largely through technology--the use. of scientific knowledge for practical45__________. The refrigerator, for example, owes its existence to a discovery that liquids take in energy when they evaporate, a phenomenon known as latent heat.A. Scientists utilize existing knowledge in new scientific investigations to predict how things will behave. For example, a scientist who knows the exact dimensions of a lens can predict how the lens will focus a beam of light. In the same way, by knowing the exact makeup and properties of two chemicals, a researcher can predict what will happen when they combine.B. For a large part of recorded history, science had little bearing on people’s everyday lives. Scientific knowledge was gathered for it sown sake, and it had few practical applications.C. During scientific investigations, scientists put together and compare new discoveries and existing knowledge. In most cases, new discoveries extend what is currently accepted, providing further evidence that existing ideas are correct.D. Tile principle of latent heat was first exploited in a practical way in 1876, and the refrigerator has played a major role in maintaining public health ever since. Tile first automobile, dating from the 1880s, made use of many advances in physics and engineering, including reliable ways of generating high-voltage sparks, while the first computers emerged in the 1940s from simultaneous advances in electronics and mathematics.E. Some forms of technology have become so well established that it is easy to forget the great scientific achievements that they represent.F. In science, important advances can also be made when current ideas are shown to be wrong. A classic case of this occurred early in the 20th century, when the German geologist Alfred Wegener suggested that the continents were at one time connected, a theory known as continental drift.G. Other fields of science also play an important role in the things we use or consume every day. Research in food technology has created new ways of preserving and flavoring what we eat. 45

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简述国务院的提案职权及其主要内容。

A patent is an exclusive right given to an inventor for his or her invention. In other words, a patent is a monopoly right given to the inventor for the invention. A patent confers on the inventor the right to price and to sell the invention in any way he or she desires, in the United States, patents are granted by the Patent Office for 17 years. Although economists generally condemn monopoly as a form of market organization since monopoly imposes costs on the economy, patents present a more subtle case for monopoly theory. Specifically, can patent monopolies be justified In general, economists complain about the costs of monopoly because they believe that the same industry could be organized competitively. A patent monopoly grant for 17 years presents a different problem. That is, the purpose of the patent system is to encourage invention. The issue is not monopoly versus competition but, more fundamentally, invention versus no invention. Is the world better off with the invention, even though it is monopolized for 17 years In other words, what are the costs and benefits of a patent Consider the simple case of a new consumer product with a positive demand, such as a camera utilizing a new exposure process. The costs of the patent monopoly are simply the deadweight costs of monopoly measured by the lost consumers’ surplus from the 17-year patent monopoly. This cost must be assessed carefully in the context of an invention, however. What are the benefits of the patent system First, there is the increase in consumer well-being brought about immediately by a desirable invention. In 17 years, the patent monopoly ends, and a second source of benefits arises: The price of cameras will fall to a competitive level, and consumers will reap the benefits of the camera at a lower price. In sum, theory of monopoly helps us to assess the costs and benefits of the patent. One can quibble about patent monopolies, arguing, for example, that they are granted for too long a time. In the end, the patent system creates goods and services and technologies that did not previously exist. In this respect it is a valuable System for the economy. The patent system also underscores the importance of property rights to ideas as a source of economic growth and progress. The second paragraph suggests strongly______.

A. the contradictory nature of the patent system
B. the importance of the patent system
C. the benefits of the patent system
D. the monopoly of the patent system

Questions 11 to 18 are based on the conversation you have just heard.

A. Candy.
B. Cigarettes.
C. Toys.
D. Books.

Immediately after the Civil War, however, the diet began to change. 46) Rail transportation increased the supply and improved the quality of the milk that reached urban centers; cold storage and refrigerator cars made possible the greater consumption of fresh vegetables, fresh fruits, and fresh fish; and commercial canning extended the range of appetizing and healthful foods. Subsequently food statistics indicated an increased consumption of dairy products, fresh fruit, fresh vegetables, sugar and syrups, coffee, tea, cocoa, and spices. Decreased consumption was shown for meats, potatoes, and grain products. 47) By and large, the American diet continued to reflect a considerable reliance upon animal products: rather than on grains. which meant that a relatively large acreage was required to feed the American public. Whereas a grain and fish diet, such as in Japan, requires only a quarter of an acre high yield cropland and no pasture per capita, the American diet requires about two and a half acres of cropland and ten acres of pasture per capita-Also it indicated a shift toward the so-called protective foods, toward those high in vitamins and proteins. 48) This change was greatly furthered by governmental food inspection ( the Pure Food and Drug Act was passed in 1906), by the increasing, use of mechanical refrigerators in the 1920’s and 1910’s and of freezers for frozen food during recent decades.In the years after World War I a food revolution took place that was reminiscent of the one that occurred after the Civil War. The output of the food manufacturing industry quadrupled from 1900 to 1920.49) In that interval, as we have mentioned earlier, home canning gave way to commercial canning and the labor of housekeeping was lightened.Fortunately most of the major dietary changes that have taken place since the middle of the nineteenth century have resulted in better nutrition for the population. In port, these shifts have taken place because of a preference for new foods rather than old, but in part, they have been made because the new foods were advocated by nutritionists. Apparently American dietary customs were not so deeply ingrained as to prevent change in the interests of better health. 50) Possibly one factor that has contributed to the readiness of Americans to accept new foods or food preparations as the general familiarity most have with a variety of regional dishes coming from many different lands. Within a small area in New York City or San Francisco, one can find restaurants specializing in French, Italian, German, Turkish, Arabian, or Chinese cuisine. And at a Chinese restaurant in the United States the chef and waiter are as likely as not to he Oriental. Possibly one factor that has contributed to the readiness of Americans to accept new foods or food preparations as the general familiarity most have with a variety of regional dishes coming from many different lands.

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