问题 单项选择题

若α1,α2,α3,β1,β2都是四维列向量,且四阶行列式|α1,α2,α3,β1|=m,|α1,α2,β2,α3|=n,则四阶行列式|α3,α2,α1,(β12)|等于( )。

A.m+n
B.-(m+n)
C.-(m+n)
D.m-n

答案

参考答案:C

解析: 由题设式|α1,α2,α3,β1|=m,式|α1,α2,β2,α3|=n
于是|α3,α2,α1,(β12)|=|α3,α2,α1,β1|+|α3,α2,α1,β2|
=|α1,α2,α3,β1|+|α1,α2,β2,α3|
=m+n=n-m

问答题 简答题

某集团公司(下称原告)以每吨2015元人民币的价格购进2479.895吨豆粕,需从大连港经水路运往广州黄埔港。

1992年8月27日,原告将货物运进大连港。

因某保险公司下属支公司(下称被告)与大连港有长期代办保险业务合同关系,大连港收到原告货物后,即于28日在《水路货物承运登记单》上加盖了被告的保险印章,并通知原告缴纳保险费。

原告按每吨1500元人民币的保险费对2479.895吨豆粕(共计39606件)向被告投保了综合险,保险总之额3719850元,并支付了保险费人民币13019元,保险合同条款按中国人民保险公司《国内水路、铁路货物运输保险条款》(摘要)规定。

该批货物于1992年8月28日开始装船。

8月30日凌晨天降大雨,因承运船第八舱液压管爆裂,致使舱盖不能关闭,造成原告已装船货物被雨淋湿。

原告要求承运人卸下381件,并告知被告货被雨淋,要求被告上船对剩余货物是否需要卸下船进行检验确认。

被告经查验,没有提出卸货意见。

当日,承运人按《运规》规定向原告出具了“8仓货物被雨淋湿,已卸下381件,余货水湿不详”的货运记录。1992年8月31日,该批货物装船完毕后即运往广州黄埔港。

9月3日,被告向原告出具了《国内水路、陆路货物运输保险单》。

船抵广州黄埔港,因泊位紧张,一直在锚地等泊,同年9月30日才靠泊卸货。

根据黄埔港理货公司理货证明和黄埔港货运记录记载,所卸下货物有6932件水湿现象,其中有370吨豆粕发生霉变。

原告即通知被告赴广州黄埔港查验货损情况。

被告派员赴黄埔港查验后,要求原告尽书采取各种补救措施,迅速处理受损货物,避免扩大损失。原告即将受损严重的370吨豆粕以每吨600元人民币的价格卖出。

按投保额扣除残值后,原告损失33万元人民币。事后,原告按保险合同约定向被告索赔,被告以货损事故系承运人责任造成的为理由拒赔。

1993年6月8日,原告向大连海事法院提起诉讼,诉称:自原告货物进大连港投保货物运输时,保险合同即告成立。

原、被告间的保险合同合法、有效,损失的后果是客观真实的,发生了保险范围内的货损事故,被告理应负赔偿责任。

要求被告赔偿130万元人民币的经济损失。

被告辩称:货损是由承运人的责任造成的,按有关规定,在限额内应由承运人按照实际损失赔偿,超过限额部分由保险公司在保险金额范围内给予补偿。

根据本案实际情况,被告向原告出具的《保险单》是在1992年9月3日,货损发生在出单之前,发生货损时,保险合同还没成立。

因此,原告要求被告按保险合同赔偿损失的理由是不成立的。

运用相关理论知识评析此案

单项选择题

Michael Porter, who has made his name throughout the business community by advocating his theories of competitive advantages, is now swimming into even more shark-infested waters, arguing that competition can save even America’s troubled health-care system, the largest in the world. Mr. Porter argues in " Redefining Health Care" that competition, if properly applied, can also fix what ails this sector.

That is a bold claim, given the horrible state of America’s health-care system. Just consider a few of its failings: America pays more per capita for health care than most countries, but it still has some 45m citizens with no health insurance at all. While a few receive outstanding treatment, he shows in heart-wrenching detail that most do not. The system, wastes huge resources on paperwork, ignores preventive care and, above all, has perverse incentives that encourage shifting costs rather than cutting them outright. He concludes that it is "on a dangerous path, with a toxic combination of high costs, uneven quality, frequent errors and limited access to care. "

Many observers would agree with this diagnosis, but many would undoubtedly disagree with this advocacy of more market forces. Doctors have an intuitive distrust of competition, which they often equate with greed, while many public-policy thinkers argue that the only way to fix America’s problem is to quash the private sector’s role altogether and instead set up a government monopoly like Britain’s National Health Service.

Mr. Porter ply disagrees. He starts by acknowledging that competition, as it has been introduced to America’s health system, has in fact done more harm than good. But he argues that competition has been introduced piecemeal, in incoherent and counter-productive ways that lead to perverse incentives and worse outcomes:" health-care competition is not focused on delivering value for patients," he says.

Mr. Porter offers a mix of solutions to fix this mess, and thereby to put the sector on a genuinely competitive footing. First comes the seemingly obvious (but as yet unrealized ) goal of data transparency. Second is a redirection of competition from the level of health plans, doctors, clinics and hospitals, to competition "at the level of medical conditions, which is all but absent". The authors argue that the right measure of "value" for the health of treatment, and what the cost is for that entire cycle. That rightly emphasizes the role of early detection and preventive care over techno-fixes, pricey pills and the other failings of today’s system.

If there is a failing in this argument, it is that he sometimes strays toward naive optimism. Mr. Porter argues, for example, that his solutions are so commonsensical that private actors in the health system could forge ahead with them profitably without waiting for the government to fix its policy mistakes. That is a tempting notion, but it falls into a trap that economists call the fallacy of the $ 20 bill on the street. If there really were easy money on the pavement, goes the argument, surely previous passers-by would have bent over and picked it up by now.

In the same vein, if Mr. Porter’s prescriptions are so sensible that companies can make money even now in the absence of government policy changes, why in the world have they not done so already One reason may be that they can make more money in the current sub- optimal equilibrium than in a perfectly competitive market--which is why government action is probably needed to sweep aside the many obstacles in the way of Mr. Porter’s powerful vision.

Mr. Porter’s argument seems to be based on the assumption that()

A. doctors do not have faith in the value of competition

B. the present health care competition is not patient oriented

C. Britain’s National Health Service is a successful example

D. health competition will do more good than harm in the long run