Questions 58 to 62 are based on the following passage:(10分) U.S.jeans maker Levi Strauss&Co.denied it was playing on consumer fears by launching aline of trousers fitted with“anti-radiation(防辐射)”pockets for mobile phones.The trousers,with alining which the makers say shields(防护物)against radiation,are designed by Dockers,a brandname of Levi Strauss.“We are not implying in any way that mobile phones are dangerous.Ourintention is not to cash in on consumer fears but provide the consumers with what they want,”Levi’s Eruopean communications manager Cedric Jungpeter said.The design was the fruit ofextensive market research showing that the fashion conscious was also health conscious.Jungpetersaid.“Thedebate is open.Although no study has proved mobile phones are harmful,no study hasproved the contrary either.”He added.Worldwide studies into the possible dangers of mobilephones produce often conflicting conclusions.A recent one carried out by Australian researchersover a three-year period showed that radio emissions from mobile phones did not trigger the growthof tumors in mice,and thereofre probable did not do so in humans either.And another Australlianstudy concluded cellular phones could foster tumor growth.Swedish research published recentlyconcluded that long-term users of first generation mobile phones faced an up to 80 percent greaterrisk of developing brain tumors than non-users.But a Danish study last year of 400,000 mobilephone users showed no increased cancer risk.
The passage focuses on_________
A．the debate on mobile phone’s radiation
B．the trousers concerned with mobile phones
C．the researchers on mobile phones’dangers
D．the fruit of worldwide studies into mobile phones
面相连
时（T为交流的周期），原线圈中的电流瞬时值为0.03A．变压器的原、副线圈的匝数比为（ ）
：3