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问题 单项选择题 A1/A2型题

下列关于蜘蛛痣的描述，不正确的是（）

A.出现的部位大多在上腔静脉分布的区域内

B.大小不等，直径可由针头大到数厘米大

C.体检发现蜘蛛痣便可诊断肝硬化

D.蜘蛛痣的发生一般认为与肝对体内雌激素的灭活作用减弱有关

E.蜘蛛痣常见于急慢性肝炎或肝硬化

答案

参考答案：C

选择题

对于在恒温的密闭容器中进行的反应：N2（g）＋O2（g）＝2NO（g），下列情况下该反应的化学反应速率保持不变的是   

A．缩小容器体积，使压强增大

B．保持体积不变，充入O2

C．保持体积不变，充入氦气

D．保持压强不变，充入氦气
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问答题

People today all over the world are beginning to hear and learn more and more about the problem of pollution. (46) Pollution is caused by either the release by man of completely new and often artificial substances into the environment, or by releasing greatly increased amounts of a natural substance, such as oil from oil tankers into the sea.
(47)The whole industrial process which makes many of the goods and machines we need and use in our daily lives, is bound to create a number of waste products which upset the environmental balance, or the ecological balance as it is also known. (48) Many of these waste products can be prevented or disposed of sensibly, but clearly while more and more new goods are produced and made complex, there will be new, dangerous wastes to be disposed of, for example, the waste products from nuclear power stations.
(49)Whatever its underlying reasons, there is no doubt that much of the pollution caused could be controlled if only companies, individuals and governments would make more efforts. In the home there is an obvious need to control litter and waste. Food comes wrapped up three or four times in packages that all have to be disposed of; drinks are increasingly sold in bottles or tins which cannot be reused. This not only causes a litter problem, but also is a great waste of resources, in terms of glass, metals and paper. Advertising helped this process by persuading many of us not only to buy things we neither want nor need, but also to throw away much of what we do buy. (50)Pollution and waste combine to be a problem every one can help to solve by cutting out unnecessary buying, excess consumption and careless disposal of the products we use in our daily lives.
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