题目

一个钢管放在V形架内，如图是其截面图，O为钢管的圆心．如果钢管的半径为25cm，∠MPN=60°，则OP=（ ）A．50cm B．25cm C．cm D．50cm 答案：【答案】A．【解析】试题分析：∵圆与V形架的两边相切，∴△OMP是直角三角形中∠OPN=∠MPN=30°，∴OP=2ON=50cm．故选A．阅读理解 　　Overseas publishers are becoming confident(有信心)in the Chinese market, a spokesman for the Press and Publications Administration(局)said yesterday. 　　He revealed(透露)that overseas publishers sold books valued at $2.33 million at the recently concluded Beijing International Book Fair. 　　“More foreigners are willing to sell books in China, and their confidence in the market is increasing. This is the result of China's progress in copyright protection,”he said. 　　Since the country joined the Bern Convention(协定)in 1992, it has strengthened the crackdown(打击)on copyright violators(违犯者). China's copyright laws are expected to be revised(修订)in accordance with advanced foreign standards. 　　The spokesman said unauthorized(未被授权的)translations of foreign books have been stopped and every publishing house has been ordered to buy copyrights with the help of agencies. 　　At the Beijing fair, the United States, the Netherlands and Britain were the three biggest sellers, with medical, economics and electronics books proving to be the most popular. 　　Chinese publishers decided to import 2,400 titles at the fair, which was attended by 35 countries and international publishing organizations. 　　Chinese publishes 100,000 books annually(每年), ranking first in the world. (1)From the first two paragraphs, we know ________. [　　] A．books published beyond China have taken up the Chinese market B．books from all over the world are popular in China C．foreign publishers are full of confidence in Chinese market D．publishing books in China has benefited overseas publishers (2)Owing to ________, overseas publishers are willing to sell books in China. [　　] A．the profits B．their confidence in the market C．the rate of interest D．China's improvement in copyright protection (3)The passage implies that ________. [　　] A．there have been no more copyright violators since 1992 B．China has taken much action against copyright violators before 1992 C．China really had copyright laws before 1992 D．China's copyright laws should be further improved (4)Which of the following is NOT true? [　　] A．Copyrights are ordered to be bought to publish translations of foreign books. B．Chinese publishers decided to export 2,400 kinds of books at the fair. C．Every year, 100,000 books are published in China, which ranks first in the world. D．Books on medicine, economics and electronics sell well at the Beijing fair.