题目内容
设有关系模式R (课程，教师，学生，成绩，时间，教室），其中函数依赖集F如下： F=｛课程→→教师，（学生，课程）→成绩，（时间，教室）→课程， （时间，教师）→教室，（时间，学生）→教室｝关系模式R的一个主键是（54），R规范化程度最高达到（55）。若将关系模式R分解为3个关系模式R1（课程，教师）、R2（学生，课程，成绩）、R3（学生，时间，教室，课程），其中R2的规范化程度最高达到（56）。 （56）处填（）。
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Questions 53 to 57 are based on the following passage: The Internet can make the news more democratic, giving the public a chance to ask questions and seek out facts behind stories and candidates, according to the head of the largest US on-line service. ’But the greatest potential for public participation is still in the future,’ Steven Case, chairman of America On-line, told a recent meeting on Journalism and the Internet sponsored by The Freedom Forum, though some other speakers say the new technology of computers is changing the face of journalism, giving reporters access to more information and their readers a chance to ask questions and turn to different sources. ’You don’t have to buy a newspaper and be confined to the four comers of that paper anymore.’ Sam Meddis, on-line technology editor at USA Today, observed about the variety of information available to computer users. But the speakers noted the easy access to the internet also means anyone can post information for others to see.’Anyone can say anything they want, whether it’s right or wrong.’ said Case. Readers have to determine for themselves who to trust. ’In a world of almost infinite voices, respected journalists and respected brand names will probably become more important, not less,’ Case said. ’The internet today is about where radio was 80 years ago, or television 50 years ago or cable 25 years ago, ’he said. But it is growing rapidly because it provides people fast access to news and a chance to comment on it. On the whole, the attitude Steven Case holds for the internet’s future development is （）
姜某，男，29岁。平素身体壮实，3天前出现纳食不佳，厌食油腻，形疲乏力，发热口渴，随后身目俱黄，黄色鲜明，腹部胀满，口苦，恶心欲吐，大便秘结，小便短少黄赤，舌质红苔黄腻，脉弦数。此时最佳治疗的方剂是
某文件系统采用多级索引结构，若磁盘块的大小为512 字节，每个块号需占3 字节，那么根索引采用一级索引时的文件最大长度为（27）K字节；采用二级索引时的文件最大长度为 （28）K 字节。 （28）处填（）。
患者大便秘结不通，面色无华，头晕目眩，心悸，唇、舌淡白，脉细涩。其治法是
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