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Until recently most astronomers believed that the space between the galaxies in our universe was a near perfect vacuum. This orthodox view of the universe is now being challenged by astronomers who believe that a heavy “rain” of gas is falling into many galaxies from the supposedly empty space around them. The gas apparently condenses into a collection of small supposedly empty space around them. The gas apparently condenses into a collection of small stars, each a little larger than the planet Jupiter. These stars vastly outnumber the other stars in a given galaxy. The amount of “intergalactic rainfall” into some of these galaxies has been enough to double their mass in the time since they formed. Scientists have begun to suspect that this intergalactic gas is probably a mixture of gases left over from the “big bang” when the galaxies were formed and gas was forced out of galaxies by supernova explosions.It is well known that when gas is cooled at a constant pressure its volume decreases. Thus, the physicist Fabian reasoned that as intergalactic gas cools, the cooler gas shrinks inward toward the center of the galaxy. Meanwhile its place is taken by hotter intergalactic gas from farther out on the edge of the galaxy, which cools as it is compressed and flows into the galaxy. The net result is a continuous flow of gas, starting as hot gases in intergalactic space and ending as a drizzle of cool gas called a “cooling flow,” falling into the central galaxy. A fairly heretical idea in the 1970’s, the cooling-flow theory gained support when Fabian observed a cluster of galaxies in the constellation Perseus and found the central galaxy, NGC 1275, to be a strange-looking object with irregular, thin strands of gas radiating from it. According to previous speculation, these strands were gases that had been blown out by an explosion in the galaxy. Fabian, however, disagreed. Because the strands of gas radiating from NGC 1275 are visible in optical photographs, Fabian suggested that such strands consisted not of gas blown out of the galaxy but of cooling flows of gas streaming inward. He noted that the wavelengths of the radiation emitted by a gas would change as the gas cooled, so that as the gas flowed into the galaxy and became cooler, it would emit not x-rays, but visible light, like that which was captured in the photographs. Fabian’s hypothesis was supported by Canizares’ determination in 1982 that most of the gas in the Perseus cluster was at a temperature of 80 million degrees Kelvin, whereas the gas immediately surrounding NGC 1275(the subject of the photographs) was at one-tenth this temperature.1. The primary purpose of the passage is to ______.2. It can be inferred from the passage that, if Fabian is correct, gas in the peripheral regions of a galaxy cluster ______.3. According to the passage, Fabian believes that gas flowing into a central galaxy has which of the following characteristics?4. The author of the passage probably mentions Canizares’ determination in order to ______.

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SOMETHING ABOUT NAPLES just seems made for comedy. The name alone conjures up pizza, and lovable, incorrigible innocents warbling “O Sole Mio”; a nutty little corner of the world where the id runs wild and the only answer to the question “Why?” appears to be “Why not?”Naples: the butter-side-down of Italian cities, where even the truth has a strangely fictitious tinge. One day a car rear-ended one of the city’s minibuses. The bus driver got out to investigate. While he stood there talking, his only passenger took the wheel and drove off. Neither passenger nor bus was ever seen again.Then there was that busy lunch hour in the central post office when a crack in the ceiling opened and postal workers were overwhelmed by an avalanche of stale croissants. As the cleaners hauled away garbage bags of moldy breakfast rolls, the questions remained: Who? Why? And what else could still be up there?But Naples actually isn’t so funny. Italy’s third largest city, with 1.1 million people, has a much darker side, where chaos reigns: bag snatching and mugging, clogged streets of stupefying confusion, where traffic moves to mysterious laws of its own through multiple intersections whose traffic lights haven’t functioned for months, maybe years—if they have lights at all. Packs of wild dogs roam the city’s main park. Nineteen policemen on the anti-narcotics squad are arrested for accepting payoffs from the Camorra, the local Mafia.To many Italians, particularly those in the wealthy, industrialized north, none of this is surprising. To them Naples means political corruption, wasted federal subsidies, rampant organized crime, appallingly large families, and cunning, lazy people who prefer to do something shady rather than honest work.Neapolitans know their reputation. “People think nothing ever gets done here,” said a young professional woman. Sometimes they say, “Surely you come from Milan. You come from Naples?”Giovanni del Forno, an insurance executive, told me about his flight home from a northern Italian city, the plane waited on the tarmac for half an hour for a gate to become available. “And I began to hear the comments around me: “Well, here we are in Naples,” he said with a wince. “These comments make me suffer.”Neapolitans may complain, but most can’t conceive of living anywhere else. The city has the intimacy, tension, and craziness of a large but intensely devoted family. The people have the same perverse pride as New Yorkers. They love even the things that don’t work, and they love being Neapolitans. They know outsiders don’t get it, and they don’t care. “Even if you go away”, one woman said, “you remain a prisoner of this city. My city has many problems, but away from it I feel bad.”This is a city in which living on the brink of collapse is normal. Naples has survived wars, revolutions, floods, earthquakes, and eruptions of nearby Vesuvius. First a wealthy colony founded by the Greeks (who called it Neapolis, or “new city”), then a flourishing Roman resort, it lived through various incarnations under dynasties of Normans, Swabians, Austrians, Spanish, and French, not to mention a glorious period as the resplendent capital of the Kingdom of the Two Sicilies.It was a brilliant, cultivated city that once ranked with London and Paris. The Nunziatella, the oldest military school in Italy, still basks in its two centuries of historic glory; the Teatro San Carlo remains one of the greatest opera houses in the world. The treasures of Pompeii grace the National Museum. Stretched luxuriantly between mountains and sea along the curving coast of the Bay of Naples, full of ornate palaces, gardens, churches, and works of art, with its mild climate and rich folklore, Naples in the last century was beloved by artists and writers. The most famous response to this magnificence was the comment by an unknown admirer, “See Naples and die.”Today that remark carries less poetic connotations. The bombardments of World War II were followed by the depredations of profiteers and politicians-for-rent who reduced the city to a demoralized shadow of itself, surviving on government handouts. Until five years ago city governments were cobbled together by warring political factions; some mayors lasted only a few months. A cholera outbreak in 1973 was followed in 1980 by a major earthquake. Its famous port has withered (though the U.S. Sixth Fleet command is still based just up the coast), industries have failed, tourists have fled, natives have moved out—it seems that only drug trafficking is booming. “Unlivable,” the Neapolitans say, “Incomprehensible”, “Martyred”.1. The two examples in the second and third paragraphs intend to show that ______.2. It can be concluded from the passage that the Northerners ______.3. The author implies that Neapolitans’ affection for the city ______.4. When the author says “Today that remark carries less poetic connotations,” he actually means that ______.

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Human migration: the term is vague. What people usually think of is the permanent movement of people from one home to another. More broadly, though, migration means all the ways—from the seasonal drift of agricultural workers within a country to the relocation of refugees from one country to another.Migration is big, dangerous, compelling. It is 60 million Europeans leaving home from the 16th to the 20th centuries. It is some 15 million Hindus, Skihs, and Muslims swept up in a tumultuous shuffle of citizens between India and Pakistan after the partition of the subcontinent in 1947.Migration is the dynamic undertow of population change: everyone’s solution, everyone’s conflict. As the century turns, migration, with its inevitable economic and political turmoil, has been called “one of the greatest challenges of the coming century.” But it is much more than that. It is, as has always been, the great adventure of human life. Migration helped create humans, drove us to conquer the planet, shaped our societies, and promises to reshape them again.“You have a history book written in your genes,” said Spencer Wells. The book he’s trying to read goes back to long before even the first word was written, and it is a story of migration.Wells, a tall, blond geneticist at Stanford University, spent the summer of 1998 exploring remote parts of Transcaucasia and Central Asia with three colleagues in a Land Rover, looking for drops of blood. In the blood, donated by the people he met, he will search for the story that genetic markers can tell of the long paths human life has taken across the Earth. Genetic studies are the latest technique in a long effort of modern humans to find out where they have come from. But however the paths are traced, the basic story is simple: people have been moving since they were people. If early humans hadn’t moved and intermingled as much as they did, they probably would have continued to evolve into different species. From beginnings in Africa, most researchers agree, groups of hunter-gatherers spread out, driven to the ends of the Earth.To demographer Kingsley Davis, two things made migration happen. First, human beings, with their tools and language, could adapt to different conditions without having to wait for evolution to make them suitable for a new niche. Second, as populations grew, cultures began to differ, and inequalities developed between groups. The first factor gave us the keys to the door of any room on the planet; the other gave us reasons to use them.Over the centuries, as agriculture spread across the planet, people moved toward places where metal was found and worked and to centers of commerce that then become cities. Those places were, in turn, invaded and overrun by people later generations called barbarians.In between these storm surges were steadier but similarly profound fides in which people moved out to colonize or were captured and brought in as slaves. For a while the population of Athens, that city of legendary enlightenment was as much as 35 percent slaves.“What strikes me is how important migration is as a cause and effect in the great world events.” Mark Miller, co-author of The Age of Migration and a professor of political science at the University of Delaware, told me recently.It is difficult to think of any great events that did not involve migration. Religions spawned pilgrims or settlers; wars drove refugees before them and made new land available for the conquerors; political upheavals displaced thousands or millions; economic innovations drew workers and entrepreneurs like magnets; environmental disasters like famine or disease pushed their bedraggled survivors anywhere they could replant hope. “It’s part of our nature, this movement,” Miller said, “It’s just a fact of the human condition.”1. Which of the following statements is INCORRECT?2. According to Kingsley Davis, migration occurs as a result of the following reasons EXCEPT ______.3. Which of the following groups is NOT mentioned as migrants in the passage?4. There seems to be a (n) ______ relationship between great events and migration.

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Superstition is a biased word. Look up almost any dictionary definition and you will see that it implies that every religion not based on reason or knowledge is called a superstition. Even the word knowledge is a two-faced word. Presumably, it is used as a synonym for reason. What it all comes down to is that people designate as superstitious what they do not think reasonable in someone else’s religion.It is true that a person’s religion must be based on some kind of knowledge. But what kind of knowledge is meant? Scientific, experimental, rational? Such knowledge is natural and maybe ethical and then it is natural religious knowledge. A person may quite easily conclude from observing the universe that only God could have produced it. That knowledge is not religion, not even if a person is bound to recognize a Creator of the universe. It is natural knowledge such as Confucius, Socrates or Zoroaster possessed.Natural religious knowledge, as is evident in the history of the human race, although it helps to make a man good, hardly suffices to keep him good, especially in times of crisis. Will such natural knowledge, for instance, sustain a man when he has suddenly lost all his money and even his wife and children? Will it offer the hope of ever seeing them again? Will it influence him gladly to sacrifice his life for his family, his country, his religion? Only a strong sense of supernatural religion, a reliance upon God, will provide the necessary courage for right action.All the great religions of the world—Christianity, Hinduism, Chinese Buddhism and Islam—have shown men the way to such courage and its resulting peace of mind and heart and peace with all men. They point to a better sort of life, mostly a life somewhere else, or, at least, an end to the troubles of this life.Christianity and Islam direct men to look up, hope for and strive after an eternal life of happiness in the possession of God. Hinduism, although it believes in reincarnations, also encourages its adherents to achieve successively higher incarnations until they achieve unity, become one with Brahman—God. Chinese Buddhism tells its followers that if they perform good deeds and have faith in Omitofoo by frequently calling upon this God of Infinite Compassion they will be rewarded by eternal life in the Western Paradise.The agnostic or the atheist thinks of all of those creeds as religious superstition. Are the agnostic and the atheist free of superstition? Hardly. Every thinking man has a natural bent for religion, for ideals above and beyond earthly ones. If he crushes his natural inclination, which is God-inspired ideals, he most likely will substitute a series of self-inspired ideals or some fad like astrology, which will become a religion for him.There is a line between religion and superstition which everyone must learn to identify, or forfeit a true direction in his life.1. According to the passage, people define superstition as ______.2. According to the author, all the great religions of the world ______.3. From the passage we are told that the atheists ______.4. Of the following suggested title, the one that most accurately sums up the passage is ______.

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The European Union revealed on January 23th how it plans to save the world. A mammoth climate-change plan spells out in detail how much pain each of its 27 members will have to bear if the EU is to meet ambitious targets set by national leaders last Match.The aim is to cut greenhouse-gas emissions by 2020 by at least a fifth, and more than double to 20% the amount of energy produced from renewable sources such as wind or wave power. If fuel from plants proves green enough, 10% of the fuel used in transport must come from biofuels by the same date. The new plan turns these goals into national targets. This will surely start much grumbling and months of horse-trading, as the European Commission’s recommendations are turned into binding law by national governments and the European Parliament.Countries with greenery in their veins are being asked to take more of the burden than newer members. Sweden, for example, is being invited to meet 49% of its energy from renewables. At the other end, Malta gets a renewables target of just 10%. It is a similar story when it comes to cutting greenhouse gases: by 2020, Denmark must cut emissions by 20% from 2005 levels; Bulgaria and Romania, the newest members, may let their emissions rise by 20%.EU leadership on climate change will not come cheap. The direct costs alone may be e 60 billion ($87 billion), or about 0.5% of total EU GDP, by 2020, said the commission’s president, Jose Manuel Barroso. But this is still presented as a bargain compared with the cost of inaction, which Mr Barroso put at ten times as high. “Oh, leading the world in the fight against climate change need not cost jobs, even in the most heavily polluting branches of heavy industry. We want to keep our industry in Europe”, insisted Mr. Barroso.The trick to achieve the seemingly impossible targets is the EU’s emissions-trading scheme (ETS). This obliges big polluters such as power companies or manufacturing giants to trade permits that allow them to emit CO2 and other climate-change nasties, within a steadily tightening overall cap. If countries such as the United States do not sign binding international agreements by 2011, then the heaviest greenhouse-gas emitters inside the EU may be given these allowances free, the commission suggests. Or, it threatens, firms outside the EU could be forced to buy ETS permits.1. To its member nations, the EU’s plan means ______.2. By using some data in paragraph 3, the author ______.3. According to Mr. Barroso, heavy industry in the EU countries will ______.4. According to the EU’s ETS, big polluters ______.

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