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设一个图书借阅管理数据库中包括三个关系模式：图书（图书编号，书名，作者，出版社，单价）读者（借书证号，姓名，性别，单位，地址）借阅（借书证号，图书编号，借阅日期，归还日期，备注）用SQL语句完成下面36-39题。建立“红星汽车厂”读者的视图RST。

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数据库的并发操作会带来哪些问题？

在奎德看来，与政策分析密切相关的政治因素主要表现在（）和（）两个方面。

英国初等学校学生的学业成绩评定主要有两大方面，一是关键阶段末的统测，二是（）

第二篇Crystal EarOne day a friend asked my．wife Jill if I wanted a hearing aid．“He certainly does．”repliedJill．After hearing about a remarkable new product．Jill finally got up the nerve to ask me if I’dever thought about getting a hearing aid．“No way,”I said．“It would make me look 20 years older．” “No。no。”she replied．”This is entirely different．It’s Crystal Ear!” Jill was right．Crystal Ear is different—not the old. Styled body worn over-the．ear aid。but all advanced personal sound system so small that it’s like contacts(隐形眼镜)for your ears．And Crystal Ear is super-sensitive and powerful．too．You will hear sounds your ears have been missing for years．Crystal Ear will make speech 10uder,and the sound is pure add natural． I couldn’t believe how tiny it is．It is smaller than the tip of my little finger and it’s almost invisible When worn．There are no wires。no behind—the．ear device．Put it in your ear and its ready—to-wear mold(形状)fits comfortably．Since it’s not too loud or too tight，you may even forget that you’re wearing it! Use it at work or at play．And if your hearing problem is worse in certain situations，use Crystal Ear only when you need it． Hearing loss，which Occurs typically prior to teenage years，progresses throughout one’s lifetime．A1though hearing loss is now the world’s number one health problem，nearly 90 percent of people suffering hearing 10SS choose to leave the problem untreated．For many millions，treating hearing 10SS in a conventional way can involve numerous office visits，expensive testing and adjustments to fit your ear．Thanks to Crystal Ear，the“sound solution”is now convenient． Almost 90 percent of people with mild hearing loss，and millions more with just a little hearing drop-off(下降)，can be dramatically helped with Crystal Ear．More over, its superior design isenergy-efficient，so batteries can last months．Crystal Ear is now available to help these people treat their hearing loss with a small hearing amplifier(放大器)． Initially the writer did not want t0 buy a hearing aid because（）

A. it would make him look old．
B. it would make him nervous．
C. it was too expensive．
D. it was old-styled．