以下对期货投机的描述，正确的是（）。 A.期货投机交易者以现货和期货两个市场为对象

在关系数据模型中，二维表的行称为元组，二维表的列称为　【8】　。

阅读理解

     George Markov was a famous writer in Bulgaria. In 1969 he suspected that he was going to be

imprisoned or killed because one of his plays was regarded as being an attack on leaders of Bulgaria.

Markov managed to reach England and got a job with the BBC, writing something in Bulgaria.

     Some of the BBC programmes were critical of life in Bulgaria. Perhaps as a result of this, Markov

received an anonymous telephone call warning him that he would be killed. In September 1978, Markov

stopped his car in London and started to walk to his office. When he was passing a bus line, a man in the

line seemed to drop his umbrella accidently. Markov felt a sudden pain in the leg.

    When Markov reached his office, he spoke about the matter to a friend. A few hours later, he began

to feel hot. He was sent to hospital and died four days later. The doctors examined his body, and they

were puzzled about the cause of his death. Scientists were asked to help and they found a tiny metal pellet

in Markov's leg. The scientists believed that the two holes in it must contain an unknown poison in them.

    A few weeks before Markov was "shot" with a poisoned pellet fired from an umbrella, another

Bulgarian had the same experience in France. Towards the end of August 1978, Kostov felt a sharp pain

in the back when he was leaving a railway station in Paris. He was ill for a few days but became well.

When news of Markov's death became known, Kostov was asked to return to hospital for examination.

Doctors found a tiny pellet in his back, but it had stuck in an area from which the poison had not been

able to spread.

     The police in both countries are still searching for the reasons why both men were attacked. They

hoped to catch their attackers.

1.Which of the statement is right about the underlined word?

A. stranger        

B. well-known    

C. friendly        

D. unknown

2. Which of the following was not mentioned in the passage?

A. George Markov was working for the BBC

B. George Markov wrote many plays at that time

C. kostov  was "shot" with a poisoned pellet

D. Both kostov and  George Markov died at last

3. According to the passage, Markov's suspicions turned out to be       

A. wrong    

B. right            

C. reasonable    

D. unreasonable

4. Who killed Markov?

A. Bulgarian  

B. not known        

C.  French      

D. British

5. We can infer that _________

A. Leaders in Bulgaria disliked  George Markov

B. The police didn't find the person who killed George Markov

C. George Markov wrote some critical plays

D. George Markov lived in Bulgaria all his life

细菌芽孢的生成是细菌繁殖的表现。

进行并发控制时，两种基本的封锁类型是 ______ 和排他锁。

近代以来欧美强国的经济地位和相互关系发生巨大变化。

材料一：伦敦，1600年人口20万，1750年，人口67.5万（占全国人口的11%）。人口的增长，相应的公共基础设施也得到发展，伦敦定期货运服务在16世纪20年代获得较大发展，伦敦还是全国的水陆交通枢纽，伦敦全国干线公路枢纽地位形成于1730—1750年间，伦敦还是全国的信贷网中心。当18世纪90年代拿破仑侵占阿姆斯特丹后（阿姆斯特丹在17世纪成为了欧洲航运和世界融资的中心，荷兰与英国和法国之间的战争，打击了处于巅峰的阿姆斯特丹），伦敦开始取代它的位置，发展为世界货币市场中心。

——摘编自马克垚《世界文明史》

材料二：1927年7月，英国、法国以及美国的中央银行行长在纽约长岛达成了一项合作协议，试图稳定当时的国际货币体系。其协议的主要内容包括美国主动调低利率，引导资金回流英国，维持英镑汇率稳定；增加美国产品出口，用低利率促进纽约金融中心地位的提高。

——节选自《大庆晚报》2009年4月25日

材料三：美国和西欧各国存在着许多共性，如共同的历史、文化、政治价值观和社会经济、政治制度等，这是它们之间建立联盟的可能条件，但并非是必要条件，必要条件是政治或经济利益上的一致。……只是在大战以后，西欧与美国都面临着一个它们认为的“共同的劲敌”——苏联！这才使它们“求同存异”结成联盟。

——《欧洲在美国心目中地位的变化》

材料四：公约的初衷并不在于要取得多大的成就，而是在它所代表的是什么……表明了战后欧洲（和美国）发生的最重大的变化——一种分享信息并在国防、安全、贸易和货币制度及其他许多领域里合作的意愿。

——《战后欧洲史》

根据材料一指出伦敦经济地位发生的变化及导致变化的因素。