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Section BPassage One Unlike the scientist, the engineer is not free to select the problem which interests him；he must solve the problems as they arise, and his solutions must satisfy conflicting requirements. Typically, the engineering solution to most problems must take into account many factors. To the engineer, efficiency means output divided by input. His job is to secure a maximum output for a given input or to secure a given output with a minimum input. The ratio may be expressed in terms of energy, materials, money, time, or man. Most commonly the denominator (分母) is money；in fact, most engineering problems are answered ultimately in dollars and cents. The emphasis on efficiency leads to the large, complex operations which are characteristic of engineering. The processing of the new antibiotic and vaccines in the test-tube stage belongs in the field of biochemistry, but when great quantities must be produced at low cost, it becomes an engineering problem. It is the desire for efficiency and economy that distinguishes ceramic engineering from the work of the potter, textile engineering from weaving, and agricultural engineering from farming. Since output equals input minus losses, the engineer must keep losses and waste to a minimum. One way is to develop uses for products which otherwise would be waste. The work of the chemical engineer in utilizing successively greater fractions of raw materials such as crude oil is well known. Losses due to friction occur in every machine and in every organization. Efficient functioning depends on good design, careful attention to operating difficulties, and lubrication of rough spots, whether they are mechanical or personal. The raw materials with which engineers work are seldom found in useful forms. Engineering of the highest type is required to conceive, design, and achieve the conversion of the energy of a turbulent mountain stream into the powerful torque(转矩) of an electric motor a hundred miles away. Similarly many engineering operations are required to change the sands of the seashore into the precise lenses which permit us to observe the minute bacteria in a drop of water and study a giant mass of stars in outer space. Which of the following can be best answered by the information about the reduction of losses and waste in engineering
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Section AQuestions 11 to 18 are based on the conversation you have just heard.
Passage Two Being a man has always been dangerous. There are about 105 males born for every 100 females, but this ratio drops to near balance at the age of maturity, and among 70-year-olds there are twice as many women as men. But the great universal of male mortality is being changed. Now boy babies survive almost as well as girls do. This means that, for the first time, there will be an excess of boys in those crucial years when they are searching for a mate. More important, another chance for natural selection has been removed. Fifty years ago, the chance of a baby (particularly a boy baby) surviving depended on its weight. A kilogram too light or too heavy meant almost certain death. Today it makes almost no difference. Since much of the variation is due to genes, one more agent of evolution has gone. There is another way to commit evolutionary suicide: stay alive, but have fewer children. Few people are as fertile as in the past. Except in some religious communities, very few women have 15 children. Nowadays the number of births, like the age of death, has become average. Most of us have roughly the same number of offspring. Again, differences between people and the opportunity for natural selection to take advantage of it have diminished. India shows what is happening. The country offers wealth for a few in the great cites and poverty for the remaining tribal peoples. The grand mediocrity of today everyone being the same in survival and number of offspring means that natural selection has lost 80% of its power in upper-middle-class Indian compared with other tribes. For us, this means that evolution is over; the biological Utopia has arrived. Strangely, it has involved little physical change. No other species fills so many places in nature. But in the past 100,000 years--even the past 100 years--our lives have been transformed but our bodies have not. We did not evolve, because machines and society did it for us. Darwin had a phrase to describe those ignorant of evolution; they "look at an organic being as a savage looks at a ship, as at something wholly beyond his comprehension". No doubt we will remember a 20th century way of life beyond comprehension for its ugliness. But however amazed our descendants may be at how far from Utopia we were, they will look just like us. What used to be the danger of a man according to the first paragraph
男性，43岁，3年采周期性发作上腹痛，疼痛多在餐后0.5～1小时出现，进食后疼痛缓解不明显。6小时前饱食后突发右上腹持续刀割样疼痛，迅速转移至右下腹和下腹部，伴有恶心、呕吐，吐后腹痛不减轻，急送急诊室。查体：体温37.7℃，脉搏120次/min，呼吸18次/min，血压80/50mmHg。腹式呼吸消失。全腹肌紧张，压痛反跳痛明显，以上腹部为重。肝浊音界缩小，肠鸣音消失，腹腔穿刺抽出血性液体 立即给病人快速补充血容量，宜首先输注
女性，58岁，农民，小学文化，已婚。因“肝内外胆管结石”于二年前行胆管空肠吻合术。三天前突然发生右上腹剧痛并伴恶心、呕吐、寒战、高热 (T.39.4℃)、全身皮肤及巩膜重度黄染，经当地医院抗炎治疗未见明显好转，转入一综合医院急诊科。查体发现：T.35.0℃、P.140次/min、R.36次/ min、BP.64/48mmHg。病人神志恍惚，表情淡漠，肢体冰凉，口唇及指端发绀，6小时尿量15ml。实验室检查：WBC23.6×109/L。诊断为急性重症胆管炎、感染性休克 其处理原则为
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