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Soot and Snow: a Hot Combination 1. New research from NASA scientists suggests emissions of black soot alter the way sunlight reflects off snow. According to a computer simulation, black soot may be responsible for 25 percent of observed global warming over the past century. 2. Soot in the higher latitudes of the Earth, where ice is more common, absorbs more of the sun’s energy and warmth than an icy, white background. Dark-colored black carbon, or soot, absorbs sunlight, while lighter colored ice reflects sunlight. 3. Soot in areas with snow and ice may play all important role in climate change. Also, if snow and ice covered areas begin melting, the warming effect increases, as the soot becomes more concentrated on the snow surface. "This provides a positive feedback, as glaciers and ice sheet smelt, they tend to get even dirtier," said Dr. James Hansen, a researcher at NASA’s Goddard Institute for Space Studies, New York. 4. Hansen found soot’s effect on snow albedo (solar energy reflected back to space), which may be contributing to trends toward early springs in the Northern Hemisphere, such as thinning Arctic sea ice, melting glaciers and permafrost. Soot also is believed to play a role in changes in the atmosphere above the oceans and land. 5. "Black carbon reduces the amount of energy reflected by snow back into space, thus heating the snow surface more than if there were no black carbon," Hansen said. Soot’s increased absorption of solar energy is especially effective in warming the world’s climate. "This forcing is unusually effective, causing twice as much global warming as a carbon-dioxide forcing of the same magnitude," Hansen noted. 6. Hansen cautioned, although the role of soot in altering global climate is substantial, it does not alter the fact that greenhouse gases are the primary cause of climate warming during the past century. Such gases are expected to be the largest climate forcing of the rest of this century. 7. The researchers found that observed warming in the Northern Hemisphere was large in the winter and spring at middle and high latitudes. These observations were consistent with the researchers’ climate model simulations, which showed some of the largest warming effects occurred when there were heavy snow cover and sufficient sunlight. A. Soot’s Role in Changes in the Climate and the Atmosphere B. Observations of Warming in the Northern Hemisphere C. Explanation of Increased Warming Effect Caused by Soot D. Effort to Reduce Snow Albedo E. Ways to Reduce Soot Emission F. Greenhouse Gases as the Main Factor of Global Warming Paragraph 4 ______
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Goal of American Education Education is all enormous and expensive part of American life. Its size is matched by its variety. Differences in American schools compared with those found in the majority of other countries lie in the fact that education here has long been intended for everyone—not just for a privileged elite. Schools are expected to meet the needs of every child, regardless of ability, and also the needs of society itself. This means that public schools offer more than academic subjects. It surprises many people when they come here to find high schools offering such courses as typing, sewing, radio repair, computer programming or driver training, along with traditional academic subjects such as mathematics, history, and languages. Students choose their curricula depending on their interests, future goals, and level of ability. The underlying goal of American education is to develop every child to the utmost of his or her own possibilities, and to give each one a sense of civic and community consciousness. Schools have traditionally played an important role in creating national unity and "Americanizing" the millions of immigrants who have poured into this country from many different backgrounds and origins. Schools still play a large role in the community, especially in the small towns. The approach to teaching may seem unfamiliar to many, not only because it is informal, but also because there is not much emphasis on learning facts. Instead, Americans try to teach their children to think for themselves and to develop their own intellectual and creative abilities. Students spend much time, learning how to use resource materials libraries, statistics and computers. Americans believe that if children are taught to reason well and to research well, they will be able to find whatever facts they need throughout the rest of their lives. Knowing how to solve problems is considered more important than the accumulation of facts. This is America’s answer to the searching question that thoughtful parents all over the world are asking themselves in the fast-moving time: "How can one prepare today’s child for a tomorrow that one can neither predict nor understand" It is implied in the passage that ______.
Goal of American Education Education is all enormous and expensive part of American life. Its size is matched by its variety. Differences in American schools compared with those found in the majority of other countries lie in the fact that education here has long been intended for everyone—not just for a privileged elite. Schools are expected to meet the needs of every child, regardless of ability, and also the needs of society itself. This means that public schools offer more than academic subjects. It surprises many people when they come here to find high schools offering such courses as typing, sewing, radio repair, computer programming or driver training, along with traditional academic subjects such as mathematics, history, and languages. Students choose their curricula depending on their interests, future goals, and level of ability. The underlying goal of American education is to develop every child to the utmost of his or her own possibilities, and to give each one a sense of civic and community consciousness. Schools have traditionally played an important role in creating national unity and "Americanizing" the millions of immigrants who have poured into this country from many different backgrounds and origins. Schools still play a large role in the community, especially in the small towns. The approach to teaching may seem unfamiliar to many, not only because it is informal, but also because there is not much emphasis on learning facts. Instead, Americans try to teach their children to think for themselves and to develop their own intellectual and creative abilities. Students spend much time, learning how to use resource materials libraries, statistics and computers. Americans believe that if children are taught to reason well and to research well, they will be able to find whatever facts they need throughout the rest of their lives. Knowing how to solve problems is considered more important than the accumulation of facts. This is America’s answer to the searching question that thoughtful parents all over the world are asking themselves in the fast-moving time: "How can one prepare today’s child for a tomorrow that one can neither predict nor understand" Which of the following best states the goal of American education
American Sports The United States is a sports-loving nation. Sports in America take a variety of forms. organized competitive struggles, which draw huge crowds to cheer their favorite team to victory; athletic games, played for recreation anywhere sufficient space is found; and hunting and fishing. Most sports are seasonal, so that what is happening in sports depends upon the time of year. Some sports are called spectator sports, as the number of spectators greatly exceeds the number playing in the game. Baseball is the most popular sport in the US. It is played throughout the spring and summer, and professional baseball teams play well into the fall. Although no other game is exactly like baseball, perhaps the one most nearly like it is the English game of cricket. Football is the most popular sport in the fall. The game originated as a college sport more than 75 years ago. It is still played by almost every college and university in the country, and the football stadiums of some o~ the largest universities seat as many as 80,000 people. The game is not the same as European football or soccer. In American football there are 11 players on each team, and they are dressed in padded uniforms and helmets because the game is rough and injuries are likely to occur. Basketball is the winter sport in American schools and colleges. Like football, basketball originated in the US and is not popular in other countries. Many Americans prefer it to football because it is played indoors throughout the winter and because it is a faster game. It is a very popular game with high schools, and in more than 20 states, state-wide high school matches are held yearly. Other spectator sports include wrestling, boxing, and horse racing. Although horseracing fans call themselves sportsmen, the accuracy of the term is questionable, as only the jockeys who ride the horses in the races can be considered athletes. The so-called sportsmen are the spectators, who do "not assemble” primarily to see the horses race, but to bet upon the outcome of each race. Gambling is the attraction of horse racing. Baseball shares many features with the English game of cricket.
Common Problems, Common Solutions The chances are that you made up your mind about smoking a long time ago—and decided it’s not for you. The chances are equally good that you know a lot of smokers—there are, after all about 60 million of them, work with them, and get along with them very well. And finally it’s a pretty safe bet that you’re open-minded and interested in all the various issues about smokers and nonsmokers—or you wouldn’t be reading this. And those three things make you incredibly important today. Because they mean that yours is the voice—not the smoker’s and not the anti-smoker’s—that will determine how much of society’s efforts should go into building walls that separate us and how much into the search for solutions that bring us together. For one tragic result of the emphasis on building walls is the diversion of millions of dollars from scientific research on the causes and cures of diseases which, when all is said and done, still strike the nonsmoker as well as the smoker. One prominent health organization, to cite but a single instance, now spends 28 cents of every publicly contributed dollar on "education" (much of it in anti-smoking propaganda) and only 2 cents on research. There will always be some who want to build walls, who want to separate people from people, and up to a point, even these may serve society. The anti-smoking wall-builders have, to give them their due, helped to make us all more keenly aware of choice. But our guess, and certainly our hope, is that you are among the far greatest number who know that walls are only temporary at best, and that over the long run, we can serve society’s interest better by working together in mutual accommodation. Whatever virtue walls may have, they can never move our society toward fundamental solutions. People who work together on common problems, common solutions, can. What does the word "wall" used in the passage mean
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