摘要：When a pear-shaped person becomes thinner, he/she loses more . A.internal fat than external fat B.external fat than internal fat C.fat above the waist D.fat below the waist 95C The idea of fighting a noise by making more noise sounds strange , but that's exactly what motor engineers are doing in Germany and some other countries. Carmakers'research and development laboratories have already proved that mixing in more noise with the help of loudspeakers can reduce the unwanted noise. Physicists have known about the technique for a long time. Sound is made up of pressure waves in the air. If two sound waves of the same frequencymix so that the highest point of one wave happens at the same time with the lowest point of the other wave, the result is no sound. Therefore, by producing a perfect copy of the noise and delaying it by half a wave cycle, we can kill the unwanted noise. Using this technique many carmakers are racing to develop noise-killing systems both inside and outside the cars. Another good thing about the use of noise-killing systems is that it saves the need for a silencer, which not only reduces the weight of a car, but also makes the motor burn less oil and work better. Some engineers believe that the noise-killing system will be used in most cars in 1996. But the carmakers haven't decided if they will put it into production because it would add several hundred dollars to the cost of their cars. 67.Which of the following gives a general idea of how the noise-killing system works? A.By producing pressure waves going in the opposite direction. B.By mixing high frequency sound waves with low frequency sound waves. C.By making copies of the unwanted sound waves and letting them out a little later. D.By mixing new sound waves with the noise and sending them out together. 68.Besides its main functionthe noise-killing system can . A.make a car lighter B.make a car quieter C.reduce the cost of a silencer D.improve the performance of a silencer 69.The noise-killing system is not yet popular mainly because . A.it increases the cost of car production B.carmakers are not sure if it is necessary C.it is still being tried out D.people still have their doubts E During the summer holidays there will be a revisedscheduleges for dining-room and library service hours and for bus schedules will be posted on the wall outside of the dining-hall. Weekly film and concert schedules, which are being arranged, will be posted each Wednesday outside of the student club. In the summer holidays, buses going to the town center will leave the main hall every hour on the half hour during the day. The dining-room will serve three meals a day from 7:00 am to 7:00 pm during the week and two meals from noon to 7:00 pm on weekends.The library will continue its usual hours during the week, but have shorter hours on Saturdays and Sundays. The weekend hours are from noon to 5:00 pm. All students who want to use the library borrowing services must have a new summer card. This announcement will also appear in the next week's student newspaper. 76.The main purpose of this announcement is to . A.tell students of important schedule changes B.tell students of new bus and library services C.show the excellent services for students D.ask students to renew their library cards 77.At which of the following times will the bus leave the main hall? A.8:00, 9:00, 10:00, 11:00 B.8:00, 9:30, 10:30, 11:30 C.8:30, 9:00, 9:30, 10:00 D.8:00, 9:30, 11:00, 12:30 78.Times for films and concerts are not listed in this announcement because . A.they are not to be announced B.they are hard to arrange C.the full list is not ready D.the full list is too long 79.In the summer holidays, the library will have . A.no special hours B.special hours on weekdays C.special hours on weekends D.special hours both on weekdays and weekends. 80.We may infer that during the summer holidays . A.the student newspaper will sell more copies B.there will be a concert or a film once a week C.many students will stay in the university D.no breakfast will be served on weekends 96上海(B) When did you last see a polar bear?On a trip to a zoo, perhaps?If you had attended a winter activity in New York a few years ago, you would have seen a whole polar bear club. These "Polar Bears" are people who meet frequently in the winter to swim in freezing cold water.That day, the air temperature was 3℃, and the water temperature was a bit higher. The members of the Polar Bear Club at Coney Island, New York are usually about the age of 60. Members must satisfy two requirements. First, they must get along well with everyone else in the group, this is very important because there are so many different kinds of people in the club. Polar Bears must also agree to swim outdoors at least twice a month from November through February. Doctors do not agree about the medical effects of cold-water swimming. Some are worried about the dangers of a condition in which the body's temperature drops so low that finally the heart stops. Other doctors, however, point out that there is more danger of a heart attack during summer swimming because the difference between the air temperature and water temperature is much greater in summer than in winter. The Polar Bears themselves are satisfied with the benefits of cold-water swimming. They say that their favorite form of exercise is very good for the circulatory systembecause it forces the blood to move fast to keep the body warm. Cold-water swimmers usually turn bright red after a few minutes in the water. A person who turns blue probably has a very poor circulatory system and should not try cold-water swimming. The main benefitsof cold-water swimming are probably mental. The Polar Bears love to swim year-round;they find it fun and relaxing. As one 70-year-old woman says. "When I go into the water, I pour my troubles into the ocean and let them float away."

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