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问题 单项选择题

"没有任何一个史学家，没有任何一本历史书没有理论、思想，其中包括那些倡导‘学术自由’的人。"这段话的主要观点是（）。

A.历史研究应该有一定的理论依据

B.历史研究必须有充分的史实证据

C.历史研究必须有统一的理论指导

D.历史研究应该有充足的史书依据

答案

参考答案：A

解析：本题考查考生论证和探讨问题的能力，学习历史的方式也是考试的重要内容。本题的重点落在"理论、思想"上。B、D项与题意强调的"理论、思想"无关；C项与"学术自由"不符。A项符合题意，当选。

单项选择题

A total of 4.6 million digital televisions have been sold, and the sales of HDTV sets have quadrupled since last year. Consumers have bought HDTVs to play their DVDs and to have clearer pictures and wide screens. Only a small percentage of the people who have purchased HDTVs, however, have actually hooked their TVs up to receive high-definition television digital signals. Perhaps television viewers are having trouble keeping up with the changes in technology. Even the manufacturers of HDTVs, like Mitsubishi, Thomson Multimedia, Sony, and Samsung seem to have a tough time learning how to make their sets work with the various digital TV formats because little standardization has been required or implemented in the industry.

Some of the HDTVs weigh over 200 lbs., and a variety of retailers offer a delivery service to the buyer’s home to help install the heavy sets. This is known as a white-glove service and usually comes with an extra fee. After HDTV purchasers get their sets home and hook them up, they will still need to work to get the digital signals to their systems. Most of the industry’s cable providers do not yet offer high~definition programing, and only about 15% of commercial television stations have switched over to even the lowest improved digital pictures. Worse yet, viewers may need to install antenna before they can even get the digital signals to their new HDTV sets. Another frustration for home-theater seekers is that the current HDTV sets allow owners only to watch high-definition programs, not to record them.

According to the first sentence, the sales of HDTV sets since last year, by the time when this article was written, had reached ().

A. 4.6 million

B. 9.2 million

C. 18.4 million

D. I do not know how many
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判断题

长期债券与短期债券相比，其投资风险和融资风险均较大。( )
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