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The burning of coal is very wasteful of energy. This can be realized when we remember that one pound to coal burned in the furnace of a power station (26) raise enough team to drive a generator (27) will produce enough current to light a one barelectric fire for three hours. On the other hand, if all the energy in the atoms of a pound of coal could be released, (28) should be enough energy to (29) all the machinery in all the factories in Britain for a month. In simpler words, all this means that one pound of any element or compound of element, if completely converted (30) energy by breaking up the atoms, would (31) the same amount of heat (32) the burning of 1,500,000 tons of coal. Scientists have calculated that if a bucket of sand from the beach could be completely (33) into energy, and if the energy so obtained was used to drive electric generators, enough (34) would be produced to supply the whole of Europe for five years. (35) other words, a bucket of sand contains enough energy to (36) a thousand million pounds’ worth of electricity. Albert Einstein was the first man to realize the vast (37) of energy locked in the atom. Einstein was also the first to show in theory how the energy of the atom might be released. Indeed without Einstein’s theory (38) was the result of many complicated mathematical calculations, there would never have been any practical (39) of nuclear power. In 1905, which was many years before other scientists really understood a great deal about atomic energy, Einstein declared that if you "destroyed" a given mass of matter, you would obtain (40) its place an enormous amount of energy. (41) support this theory, Einstein worked (42) what is probably the most important equation in the history of mathematics. It was (43) no means a complicated equation, but in fact a very simple (44) . Here it is: E=MC2. Turned into simple language, Einstein’s equation means that energy(E) is equal (45) mass(M) multiplied by the speed of light(C) squared(C2).
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Amtrak (美国铁路客运公司) was experiencing a downswing in ridership (客运量) along the lines comprising its rail system. Of major concern to Amtrak and its advertising agency DDB Needham, were the long-distance western routes where ridership had been declining significantly. At one time, trains were the only practical way to cross the vast areas of the west. Trains were fast, very luxurious, and quite convenient compared to other forms of transportation existing at the time. However, times change and the automobile became America’s standard of convenience. Also, air travel had easily established itself as the fastest method of traveling great distances. Therefore, the task for DDB Needham was to encourage consumers to consider other aspects of train travel in order to change their attitudes and increase the likelihood that trains would be considered for travel in the west. Two portions of the total market were targeted: anxious fliers—those concerned with safety, relaxation, and cleanliness and travel-lovers—those viewing themselves as relaxed, casual, and interested in the travel experience as part of their vacation. The agency then developed a campaign that focused on travel experiences such as freedom, escape, relaxation, and enjoyment of the great western outdoors. It stressed experiences gained by using the trains and portrayed western train trips as wonderful adventures. Advertisements showed pictures of the beautiful scenery that could be enjoyed along some of the more famous western routes and emphasized the romantic names of some of these trains (Empire Builder, etc.).These ads were strategically placed among family-oriented TV shows and programs involving nature and America in order to most effectively reach target audiences. Results were impressive. The Empire Builder, which was focused on in one ad. enjoyed a 15 percent increase in profits on its Chicago to Seattle route. According to the passage, the Empire Builder enjoyed an increase in ridership and profits because ______.
Like many of my generation, I have a weakness for hero worship. At some point, however, we all begin to question our heroes and our need for them. This leads us to ask: What is a hero Despite immense differences in cultures, heroes around the world generally share a number of characteristics that instruct and inspire people. A hero does something worth talking about. A hero has a story of adventure to tell and a community who will listen. But a hero goes beyond mere fame. Heroes serve powers or principles larger than themselves. Like high voltage transformers, heroes take the energy of higher powers and step it down so that it can be used by ordinary people. The hero lives a life worthy of imitation. Those who imitate a genuine hero experience life with new depth, enthusiasm, and meaning. A sure test for would be heroes is what or whom do they serve What are they willing to live and die for If the answer or evidence suggests they serve only their own fame, they may be famous persons but not heroes. Madonna and Michael Jackson are famous, but who would claim that their fans find life more abundant Heroes are catalysts (催化剂) for change. They have a vision from the mountaintop. They have the skill and the charm to move the masses. They create new possibilities. Without Gandhi, India might still be part of the British Empire. Without Rosa Parks and Martin Luther King, Jr., we might still have segregated (隔离的) buses, restaurants, and parks. It may be possible for large scale change to occur without leaders with magnetic personalities, but the pace of change would be slow, the vision uncertain, and the committee meetings endless. Gandhi and Martin Luther King are typical examples of outstanding leaders who ______.
Questions 22-25 are based on the following conversation. What does the woman say about parking
what must the woman do to have a house in the country
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