单项选择题

某地区的队列研究如下─────────────────────────死亡率(1/10万人)──────────肺 癌 冠心病─────────────────────────非吸烟组 10 100吸烟组(1)20岁以前开始吸烟 60 150(2)20岁以后开始吸烟 40 130─────────────────────────下列论述哪项是错误的

A.不论哪一组都是肺癌的吸烟相对危险性大于冠心病的吸烟相对危险性
B.吸烟者总的相对危险性,肺癌的是:(40+60)÷2/10=5.0(冠心病用同样方法计算的是1.4)
C.肺癌的吸烟特异危险性与冠心病的吸烟特异危险性相等
D.肺癌的吸烟AR%与冠心病的吸烟AR%则不相等
E.吸烟开始年龄与两种疾病死亡率有关
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【案例分析题】

World Trade Organization Director-general Renato Ruggiero predicted that the WTO would boost global incomes by $1trillion in the next ten years.The pact paves the way for more foreign investment and competition in telecom markets.Many governments are making telecom deregulation a priority and making it easier for outsiders to enter the telecmmunication business.
The pace varies widely.The U.S.and Britain are well ahead of the pack,while Thailand won’t be fully open until 2006.Only 20%of the $601billion world market is currently open to competition.That should jump to about 75%in a couple of years-largely due to the Telecom Act in the U.S.last year that deregulated local markets,the opening up of the European Union’s markets from Jan.1,1998and the deregulation in Japan.The WTO deal now provides a forum for the inevitable disputes along the way.It is also symbolic:the first major trade agreement of the post-industrial age.Instead of being obsessed with textile quotas,the WTO pact is proof that governments are realizing that in an information age,telecom is the oil and steel of economies in the future.Businesses around the world are already spending more in total on telecom services than they do on oil.
Consumers,meanwhile,can look forward to a future of lower prices—by some estimates,international calling rates should drop 80%over several years—and better service.Thanks in part to the vastly increased call volume carded by the fiber-optic cables that span the globe today,calling half a world away already costs little more than telephoning next door.The monopolies can no longer set high prices for international calls in many countries.In the U.S.,the world’s most fiercely competitive long distance market,frequent callers since last year have been paying about 12cents a minute to call Britain,a price not much more than domestic rates.
The new competitive environment on the horizon means more opportunities for companies from the U.S.and U.K.in particular because they have plenty of practice at the rough-and-tumble of free markets.The U.S.lobbied hard for the WTO deal,confident that its firms would be big beneficiaries of more open markets.Britain bas been deregulated since 1984but will see even more competition than before:in December,the government issued 45new international licenses to join British Telecom so that it will become a strong competitor in the international market.However,the once-cosseted industry will get rougher worldwide.Returns on capital will come down.Risks will go up.That is how free ,markets work.It will look like any other business.

Which of the following statements can best describe the main theme of the passage?()

A.There is a great potential in the world telecom market.
B.The WTO pact has boosted a rapid development of telecom all over the world.
C.The WTO pact has opened up bigger telecom markets to competition.
D.Governments have realized the importance of telecommunication.

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