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以下是创建部分关系表的SQL语句，请将空缺部分补充完整。CREATE TABLE客户(客户号 CHAR(5) (a) ，姓名 CHAR(30)，性别 CHAR(2) (b) ，地址 CHAR(30)，邮编 CHAR(6))；CREATE TABLE 订单(订单号CHAR(4)，时间 CHAR(10)，金额 NUMBER(6,2)，客户号CHAR(5)NOTNULL，PRIMARY KEY(订单号)，(c) ；

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The desire to use language as a sign of national identityis a very natural one, and in result language has played a (1) prominent part in national moves. Men have often felt the (2) need to cultivate a given language to show that they aredistinctive from another race whose hegemony they resent. (3) At the time the United States split off from Britain, for (4) example, there were proposals that independence should belinguistically accepted by the use of a different language from (5) those of Britain. There was even one proposal that Americans (6) should adopt Hebrew. Others favoured the adoption ofGreek, though, as one man put it, things would certainly besimpler for Americans if they stuck on to English and made (7) the British learn Greek. At the end, as everyone knows, the (8) two countries adopted the practical and satisfactory solutionof carrying with the same language as before. (9) Since nearly two hundred years now, they have shown (10) the world that political independence and national identitycan be complete without sacrificing the enormous mutualadvantages of a common language. 9（）

The Popularity of EnglishⅠ. Present status of EnglishA. English as a native/first languageB. English as a lingua franca: a language for communicationamong people whose（1）are differentC. Number of people speaking English as a first or a second language:— 320—380 million native speakers— 250—（2）million speakers of English as a secondLanguageⅡ. Reasons for the popular use of EnglishA. （3）reasons— the Pilgrim Fathers brought the language to America;— British settlers brought the language to Australia;— English was used as a means of control in（4）B. Economic reasons— spread of（5）— language of communication in the international business communityC. （6）in international travel— use of English in travel and tourism— signs in airports— language of announcement— language of（7）D. Information exchange— use of English in the academic world— language of（8）or journal articlesE. Popular culture— pop music on（9）— films from the USAⅢ. Questions to think aboutA. Status of English in the futureB. （10）of distinct varieties of English 7（）

海路贸易是通过海上运输(各类船舶)的国际贸易。( )

A. 对
B. 错

给出上述各关系模式的主键，以及投保单关系模式的函数依赖。