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某地区从准备参加2005年高考的学生中，随机抽查了150人，发现其中有6人购买了假冒2B铅笔。为了估计全地区参加高考学生中买到假冒2B铅笔的人数比例，请依次从下列各题的备选答案中，选出正确答案。
下列对抽样调查有关问题表述正确的有( )。
D.6人为该项调查的全部样本

A.抽样调查必须按随机原则抽取样本
B.根据样本资料可以推断总体数值
C.上述被调查的150人为该项调查研究的总体

【参考答案】

AB
解析：抽样调查是一种非全面调查，它是按照随机原则从调查总体中抽出一部分单位 (在抽样调查中称作样本单位)进......

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Flirt With SuicideThe life of David Woods was the stuff of an Australian boy's dream. He played professional rugby league football in a country that treats athletes as, idols. At 29, he had a loving family, a girlfriend, a 3-month-old baby, plenty of money, everything to live for. And for inexplicable reasons, nothing to live for. On New Year's Eve, Woods called his mother to announce that he had signed a new contract with his team, Golden Coast, recalls his elder brother, Tony. The next morning, he ran a hose from the exhaust pipe to the window of his Mitsubishi sedan (轿车) and gasses himselF.His family still has no idea why.The death of David Woods came as a wake-up call to Australia, which is often voted as the ideal place to bring up kids. But the sun, the beaches and the sporting culture are the cheery backdrop to a disturbing trend: young Australian men are now killing themselves at the rate of one a day--triple the rate of 30 years ago. Though most Australians aren't particularly suicidal, their boys arE.In 1990 suicide surpassed car accidents as the leading cause of death among males aged 15 to 24. Fun-loving Australia is now far worse off than Asian nations known for strict disciplinE.The yearly suicide rate for young Australian males is 2.5 times higher than in Japan, Hong Kong, or SingaporE.Possible Causes for SuicideWhy boys? A nation of wide-open spaces and rugged individualism, Australia still idolizes the film star Gary Cooper model of masculinity: the strong, silent type who never complains, who always gets the job donE.In recent years schools and social institutions have concentrated on creating new opportunities for equality for girls--while leaving troubled boys with the classic command of the Australian father: pull yourself together. It's past time to take a much closer look at the lives of young men, some researchers arguE.'People think, 'My kids aren't doing drugs, my kids are safe at home',' says psychiatrist John Tiller of Melbourne University, who studied 148 suicides and 206 attempts in the state of VictoriA.'They are wrong.'The Haywards, a comfortably well-off family in Wyong, north of Sydney, figured they were dealing with the normal problems of troubled teenhooD.Their son Mark had put up a poster of rock star Kurt Cobain, a 1994 suicide victim, along with a Cobain quote: 'I hate myself and I want to diE.' 'From the age of 12, Mark had his ups and downs--mood swings, depression and low self-esteem,' says his father. The Haywards sent Mark to various counselors, none of whom warned that he had suicidal tendencies. By last year Mark was 19, fighting bouts (回合) of unemployment and a drug problem. He tried church, struggling to do the right thing. Last September he dropped out a detoxification (戒毒) program, and apologized to his parents. 'I've let you down again.' A few days later, his mother found Mark's body in bush-land near their homE.In retrospect, Mark Hayward's struggles were far from uncommon. The number of suicides tends to keep pace with the unemployment rate, which for Australians between 15 and 19 has risen from 19 percent in 1978, the first year data were collected, to 28 percent last year. Suicide is especially high among the most marginal: young Aboriginal (土著的) men, isolated by poverty, alcoholism and racism. As in other developed countries, Australian families have grown less cohesive in recent years, putting young men out into the world at an earlier agE.Those who kill themselves often think 'it'll make it easier for the parents by not being there'.The deeper mystery is why the universal anguish of growing up should have such particularly devastating effects in AustraliA.One answer is that the country allows easier access to guns than most other developed Asian countries. (One exception is neighboring New Zealand, where guns are as easy to find, and the suicide rate among yA.YB.NC.NG

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听力原文： By Paul Abrahams in TokyoResults from Japan's largest petrochemicals companies for the year to March 31st reflect the crisis facing a sector plagued by sluggish domestic demand, over capacity, plunging prices and the appreciation of the yen.News of the sector's dire trading position follow this week's decision by Showa Denko to sell its poly styrene business.The company, a marginal manufacturer, sold its 30,000 tonnes a year Kawasaki Plant to Asahi Chemical, Japan's largest polystyrene manufacturer with capacity of about 333,000 tonnes a year, equivalent to about 25 per cent of the market. The move was the latest in a series of alliances and mergers as the troubled industry restructures.Mitsubishi Petrochemical, the country's biggest plastics group, reported a loss of Y 8.39 bn ($80m) compared with pre-tax profits last year of Y 8.25 bn. The group made an operating loss of Y 13.8 bn, the first since 1982. The poor result came despite cost cutting measures, lower raw material prices, and Y 4 bn worth of profits from equity sales.Turnover fell 12.2 per cent from Y 372 bn to Y 326 bn, as prices and volumes declineD.Earnings per share, which reached Y 52.5 in 1991, fell to a loss per share of Y 9.44. The group, which is scheduled to merge with Mitsubishi Kasei on October 1st, cut its dividend from Y 8 per share to Y 4.Mitsubishi Kasei's pre-tax profits fell 76. 8 per cent from Y 9.3 bn last year to Y 2.2 bn. The group reported its first operating loss in 40 years at Y 467 m, and only managed to post positive pre-tax results by selling Y15.7 bn worth of equities. Turnover fell 1.8 per cent, the fourth yearly decline, to Y696 bn. The dividend was halved to Y 3 per sharE.Mr. Morihisa Takano, managing director, said the newly merged group would generate pre-tax profits of Y 10 bn on sales of Y 55 bn during the year to March 1995.He predicted petrochemicals prices would bottom out during the summer. No decision had been made a bout the dividend, but the new company could pass it during the current year, the pre-tax profits at Mitsui Petrochemical Industries, Japan's biggest polyethylene maker, plunged 75 per cent from Y 9 bn to Y 2.26bn on sales down 9.3 per cent at Y 272 bn. The company blamed poor demand for the slump which offset the benefits of cost-cutting measures. The dividend is unchanged at Y 6 per sharE.The group forecasts pre-tax profits for the current year marginally up at Y 3 bn on turnover of Y 276 bn.Shin-Etsu, one of Japan's biggest makers of poly vinyl chloride, reported profits down 26.1 per cent from Y 17.6 bn to Y 13 bn. Sales increased 0.2 per cent from Y 275 bn to Y 276 bn. Net profits fell 26.6 per cent to Y 7.08 bn, or Y 21.85 per sharE.The group maintained the final dividend at Y3.75, making the full-year pay out Y7.5 per sharE.Shin-Etsu forecasts pre-tax profits for the cur rent year of Y 15.5 bn on sales of Y 277 bn.The outlook for the petrochemicals industry remains bleak. The imbalance between supply and demand for ethylene, the basic building block of petrochemicals, is about 2.8m tonnes of ethylene and is set to deteriorate further this year.A massive 700,000-tonne-a-year ethylene complex owned by Maruzen, Mitsui Petrochemical and Sumitomo Chemical comes on stream later this year and Mitsubishi Petrochemical is also commissioning a new 300,000-tonne-a-year plant this year.?You will hear a report presented by a journalist from Tokyo. He talks about the difficult situations met by Japanese chemical groups. He gives some important figures of four biggest chemical groups in Japan.?For each question 23-30 mark one letter (A, B or C) for the correct answer?After you have listened once, replay he recording.The crisis met by Japanese chemical groups is caused byA.over capacityB.high pricesC.high cost

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