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案例分析题Question 41- 50: In Death Valley, California, one of the hottest, most arid places in North America, there is much salt, and salt can damage rocks impressively. Inhabitants of areas elsewhere, where streets and highways are salted to control ice, are familiar with the resulting rust and deterioration on cars. That attests to the chemically corrosive nature of salt, but it is not the way salt destroys rocks. Salt breaks rocks apart principally by a process called crystal prying and wedging. This happens not by soaking the rocks in salt water, but by moistening their bottoms with salt water. Such conditions exist in many areas along the eastern edge of central Death Valley. There, salty water rises from the groundwater table by capillary action through tiny spaces in sediment until it reaches the surface. Most stones have capillary passages that suck salt water from the wet ground. Death Valley provides an ultra-dry atmosphere and high daily temperatures, which promote evaporation and the formation of salt crystals along the cracks or other openings within stones. These crystals grow as long as salt water is available. Like tree roots breaking up a sidewalk, the growing crystals exert pressure on the rock and eventually pry the rock apart along planes of weakness, such as banding in metamorphic rocks, bedding in sedimentary rocks, or preexisting or incipient fractions, and along boundaries between individual mineral crystals or grains. Besides crystal growth, the expansion of halite crystals(the same as everyday table salt) by heating and of sulfates and similar salts by hydration can contribute additional stresses. A rock durable enough to have withstood natural conditions for a very long time in other areas could probably be shattered into small pieces by salt weathering within a few generations. The dominant salt in Death Valley is halite, or sodium chloride, but other salts, mostly carbonates and sulfates, also cause prying and wedging, as does ordinary ice. Weathering by a variety of salts, though often subtle, is a worldwide phenomenon. Not restricted to arid regions, intense salt weathering occurs mostly in salt-rich places like the seashore, near the large saline lakes in the Dry Valleys of Antarctica, and in desert sections of Australia, New Zealand, and central Asia. According to the passage, which of the following is true about the effects of salts on rocks（）
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案例分析题Question 1-10 All mammals feed their young. Beluga whale mothers, for example, nurse their calves for some twenty months, until they are about to give birth again and their young are able to find their own food. The behavior of feeding of the young is built into the reproductive system. It is a nonelective part of parental care and the defining feature of a mammal, the most important thing that mammals-- whether marsupials, platypuses, spiny anteaters, or placental mammals -- have in common. But not all animal parents, even those that tend their offspring to the point of hatching or birth, feed their young. Most egg-guarding fish do not, for the simple reason that their young are so much smaller than the parents and eat food that is also much smaller than the food eaten by adults. In reptiles, the crocodile mother protects her young after they have hatched and takes them down to the water, where they will find food, but she does not actually feed them. Few insects feed their young after hatching, but some make other arrangement, provisioning their cells and nests with caterpillars and spiders that they have paralyzed with their venom and stored in a state of suspended animation so that their larvae might have a supply of fresh food when they hatch. For animals other than mammals, then, feeding is not intrinsic to parental care. Animals add it to their reproductive strategies to give them an edge in their lifelong quest for descendants. The most vulnerable moment in any animal’s life is when it first finds itself completely on its own, when it must forage and fend for itself. Feeding postpones that moment until a young animal has grown to such a size that it is better able to cope. Young that are fed by their parents become nutritionally independent at a much greater fraction of their full adult size. And in the meantime those young are shielded against the vagaries of fluctuating of difficult-to-find supplies. Once a species does take the step of feeding its young, the young become totally dependent on the extra effort. If both parents are removed, the young generally do no survive. The word "provisioning" in line 13 is closest in meaning to （）
简述计算机存储器分类，说明CPU读取数据的顺序；若用十六进制数给某存储器的各个字节编地址，其地址编号是从0000到FFFF，计算该存储器的容量。
案例分析题Question 32-40: Overland transport in the United States was still extremely primitive in 1790. Roads were few and short, usually extending from inland communities to the nearest river town or seaport. Nearly all interstate commerce was carried out by sailing ships that served the bays and harbors of the seaboard. Yet, in 1790 the nation was on the threshold of a new era of road development. Unable to finance road construction, states turned for help to private companies, organized by merchants and land speculators who had a personal interest in improved communications with the interior. The pioneer in this move was the state of Pennsylvania, which chartered a company in 1792 to construct a turnpike, a road for the use of which a toll, or payment, is collected, from Philadelphia to Lancaster. The legislature gave the company the authority to erect tollgates at points along the road where payment would be collected, though it carefully regulated the rates. (The states had unquestioned authority to regulate private business in this period.) The company built a gravel road within two years, and the success of the Lancaster Pike encouraged imitation. Northern states generally relied on private companies to build their toll roads, but Virginia constructed a network at public expense. Such was the road building fever that by 1810 New York alone had some 1,500 miles of turnpikes extending from the Atlantic to Lake Erie. Transportation on these early turnpikes consisted of freight carrier wagons and passenger stagecoaches. The most common road freight carrier was the Conestoga wagon, a vehicle developed in the mid-eighteenth century by German immigrants in the area around Lancaster, Pennsylvania. It featured large, broad wheels able to negotiate all but the deepest ruts and holes, and its round bottom prevented the freight from shifting on a hill. Covered with canvas and drawn by four to six horses, the Conestoga wagon rivaled the log cabin as the primary symbol of the frontier. Passengers traveled in a variety of stagecoaches, the most common of which had four benches, each holding three persons. It was only a platform on wheels, with no springs; slender poles held up the top, and leather curtains kept out dust and rain. In 1790 most roads connected towns in the interior of the country with（）
案例分析题Question 11-21: Printmaking is the generic term for a number of processes, of which woodcut and engraving are two prime examples. Prints are made by pressing a sheet of paper (or other material) against an image-bearing surface to which ink has been applied. When the paper is removed, the image adheres to it, but in reverse. The woodcut had been used in China from the fifth century A.D. for applying patterns to textiles. The process was not introduced into Europe until the fourteenth century, first for textile decoration and then for printing on paper. Woodcuts are created by a relief process; first, the artist takes a block of wood, which has been sawed parallel to the grain, covers it with a white ground, and then draws the image in ink. The background is carved away, leaving the design area slightly raised. The woodblock is inked, and the ink adheres to the raised image. It is then transferred to damp paper either by hand or with a printing press. Engraving, which grew out of the goldsmith’s art, originated in Germany and northern Italy in the middle of the fifteenth century. It is an intaglio process (from Italian intagliare, "to carve"). The image is incised into a highly polished metal plate, usually copper, with a cutting instrument, or burin. The artist inks the plate and wipes it clean so that some ink remains in the incised grooves. An impression is made on damp paper in a printing press, with sufficient pressure being applied so that the paper picks up the ink. Both woodcut and engraving have distinctive characteristics. Engraving lends itself to subtle modeling and shading through the use of fine lines. Hatching and cross-hatching determine the degree of light and shade in a print. Woodcuts tend to be more linear, with sharper contrasts between light and dark. Printmaking is well suited to the production of multiple images. A set of multiples is called an edition. Both methods can yield several hundred good-quality prints before the original block or plate begins to show signs of wear. Mass production of prints in the sixteenth century made images available, at a lower cost, to a much broader public than before. According to the passage, what do woodcut and engraving have in common（）
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