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Electromagnetic Energy 1. White light seems to be a combination of all colors. The energy that comes from a source of light is not limited to the kind of energy you can see. Heat is given off by a flame or an electric light. On a cloudy day it is possible to get a sunburn even though you feel cool. Visible light and the kind of energy that produce warmth and sunburn are examples of electromagnetic energy. 2. The sun is 93 million miles from the earth. Yet we can use energy from the sun because electromagnetic energy travels through space. 3. Many other kinds of energy are also types of electromagnetic energy. Radio, television, and radar signals travel from transmitters to receivers as low-energy electromagnetic waves. Infrared (红外的) radiation is an electromagnetic wave. When it is absorbed by matter, heat is produced. Waves of infrared and visible light have more energy than waves of radio, television, or radar. Ultraviolet rays (紫外线) and X-rays are electromagnetic waves with even greater amounts of energy. Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is useful in killing certain disease organisms. X-rays and gamma rays have so mush energy that they travel right through solid objects. They can be used to detect and treat cancer. X-rays are used in industry to find hidden cracks in metal, and in medicine to reveal broken bones. 4. Usually we use electricity to generate electromagnetic energy. The source of most of our energy is the sun. Heat from the sun causes water to evaporate. When the water fails to the earth as rain, some of it is trapped behind dams and then used to operate electric generators. Other generators are powered by coal, but the energy stored in coal came from the sun, too. 5. Until recently, the source of the tremendous amount of energy given off by the sun was a puzzle. If the sun depended on chemical reactions, it would have used up all its energy long ago. Experiments with electromagnetic radiation led to the theory that mass can be converted into energy. About forty years after the theory was proposed, nuclear energy was harnessed (利用) by man. Chemical energy comes from electron (电子) rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemical reactions, nuclear reactions release millions of times more energy per pound of fuel. We now believe that the sun’s energy comes from the nuclear reactions in which hydrogen is changed into helium (氦). 6. Nuclear energy is beginning to compete with coal as an economical source of power to generate electricity. It is also being used to operate engines in large ships. Scientists continue to seek new and better methods of obtaining and using energy. A. Nuclear reactions as the lasting source of the sun’s energy B. The most important source of energy C. Types of electromagnetic energy D. The machines used for energy generation E. Seeking new sources of energy F. The use of ultraviolet radiation in medicine Paragraph 6 ______.
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The Smog (烟雾) For over a month, Indonesia was in crisis. Forest fires raged out of control as the country suffered its worst drought for 50 years. Smoke from the fires mixed with sunlight and hot dry air to form a cloud of smog. This pollution quickly spread and within days it was hanging over neighbouring countries including Malaysia, Singapore and Thailand. When the smoke combined with pollution from factories and cars, it soon became poisonous (有毒的). Dangerous amounts of CO became trapped under the smog and pollution levels rose. People wheezed (喘息) and coughed as they left the house and their eyes watered immediately. The smog made it impossible to see across streets and whole cities disappeared as grey soot (烟灰) covered everything. In some areas, water was hosed (用胶管浇) from high-rise city buildings to try and break up the smog. Finally, heavy rains, which came in November. Put out the fires and clear the air. But the environmental costs and health problems will remain Many people from South-Eastern Asian cities already suffer from breathing huge amounts of car exhaust fumes (汽车排放的废气) and factory pollution. Breathing problems could well increase and many non-sufferers may have difficulties for the first time. Wildlife has suffered too. In lowland forests, elephants, deer, and tigers have been driven out of their homes by smog. But smog is not just an Asian problem. In fact, the word was first used in London in 1905 to describe the mixture of smoke and thick fog. Fog often hung over the capital. Sometimes the smog was so thick and poisonous that people were killed by breathing problems or in accidents. About 4,000 Londoners died within five days as a result of thick smog in 1952. The word "smog" first appeared in 1952.
The Smog (烟雾) For over a month, Indonesia was in crisis. Forest fires raged out of control as the country suffered its worst drought for 50 years. Smoke from the fires mixed with sunlight and hot dry air to form a cloud of smog. This pollution quickly spread and within days it was hanging over neighbouring countries including Malaysia, Singapore and Thailand. When the smoke combined with pollution from factories and cars, it soon became poisonous (有毒的). Dangerous amounts of CO became trapped under the smog and pollution levels rose. People wheezed (喘息) and coughed as they left the house and their eyes watered immediately. The smog made it impossible to see across streets and whole cities disappeared as grey soot (烟灰) covered everything. In some areas, water was hosed (用胶管浇) from high-rise city buildings to try and break up the smog. Finally, heavy rains, which came in November. Put out the fires and clear the air. But the environmental costs and health problems will remain Many people from South-Eastern Asian cities already suffer from breathing huge amounts of car exhaust fumes (汽车排放的废气) and factory pollution. Breathing problems could well increase and many non-sufferers may have difficulties for the first time. Wildlife has suffered too. In lowland forests, elephants, deer, and tigers have been driven out of their homes by smog. But smog is not just an Asian problem. In fact, the word was first used in London in 1905 to describe the mixture of smoke and thick fog. Fog often hung over the capital. Sometimes the smog was so thick and poisonous that people were killed by breathing problems or in accidents. About 4,000 Londoners died within five days as a result of thick smog in 1952. The forest animals haven’t been affected by the smog.
相对于其他金融机构，商业银行业务最典型的特征是______。
Benefited or Hurt For the most part, it seems, workers in rich countries have little to fear from globalization, and a lot to gain. But is the same thing true for workers in poor countries The answer is that they are even more likely than their rich country counterparts to benefit, because they have less to lose and more to gain. Orthodox economics takes an optimistic line on integration and the developing countries. Openness to foreign trade and investment should encourage capital to flow to poor economies. In the developing world, capital is scarce, so the returns on investment there should be higher than in the industrialized countries, where the best opportunities to make money by adding capital to labor have already been used up. If pool countries lower their barriers to trade and investment, the theory goes: rich foreigners will want to send over some of their capital. If this inflow of resources arrives in the form of loans or portfolio investment, it will supplement domestic savings and loosen the financial constraint on additional investment by local companies. If it arrives in the form of new foreign controlled operations, FDI, so much the better: this kind of capital brings technology and skills from abroad packaged along with it, with less financial risk as well. In either case, the addition to investment ought to push incomes up, partly by raising the demand for labor and partly by making labor more productive. This why workers in FDI receiving countries should be in an even better position to profit from integration than workers in FDI sending countries. Also, with or without inflows of foreign capital, the same static and dynamic gains from trade should apply in developing countries as in rich ones. This gain from trade logic often arouses suspicion, because the benefits seem to come from nowhere. Surely one side or the other must lose. Not so. The benefits that a rich country gets though trade do not come at the expense of its poor country trading partners, or vice versa. Recall that according to the theory, trade is a positive sum game. In all these transactions, sides exporters and importers, borrowers and lenders, shareholders and workers can gain. Which of the following statements is correct
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