题目内容
某公司需建立产品信息数据库，经调查其业务要求如下： Ⅰ．一种产品可以使用多个不同种类的部件，也可以使用多个不同种类的零件；一种部件至少被用在一种产品中；一种部件可以由多个不同种类的零件组成；一种零件至少被用在一种产品或一种部件中。 Ⅱ．对于一种具体的部件，要记录这种部件使用的各种零件的数量。 Ⅲ．对于一种具体的产品，要记录这种产品使用的各种部件数量和各种零件数量，但部件所使用的零件数量不计入该种产品的零件数量。 Ⅳ．一个供应商可供应多种零件，但一种零件只能由一个供应商供应。 根据以上业务要求，某建模人员构建了如下E-R图： 此E-R图中的实体的属性完整，但实体、联系的设计存在不合理之处。 根据重构的E-R图给出符合3NF的关系模式，并标出每个关系模式的主码和外码。
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Task 3The difficulties that would have to be encountered by anyone who attempted to explore the Moon would be incomparably greater than those that have to be faced in the endeavor to reach the summit of Mount Jolmo Lungma. In two respects only would the lunar explorer have the advantage. In the first place movement would be less fatiguing because the gravitational pull of the Moon is not very great, the weight of the Moon being only about one - eightieth of that of the Earth. If the Moon had an atmosphere like that of the Earth, a man playing golf on the Moon would find that he could drive his ball for a mile without much difficulty. The second advantage the lunar explorer would have over the climbers on Mount Jolmo Lungma would be the absence of strong wind to contend against. The Moon having no atmosphere, there can be no wind nor, of course, can there be any noise, for sound is carried by the air. The Moon is a world that is completely still and where utter silence prevails. Walking on the Moon is（）.
What is the woman doing（）
All over the world (1) suggests a picture of the public schools, and it suggests (2) the name like Eton. Actually Eton is a public school. And the best known of the public schools are (3) ,but independent and (4) taking boys from the age of (5) . (6) form is a very small part of (7) secondary, education; only about (8) English boys goes to a public school, and one out of 1,500 goes to Eton. However it is still true that if an English parents have enough money to (9) to send their children to an independent school they (10) . 1（）
Section ADirections: In this section, you will hear 10 short conversations. At the end of each conversation, a question will be asked about what was said. The conversation and the question will be spoken only once. After the question there will be a pause of about 15 seconds. During the pause, you must read the 4 suggested answers marked A), B), C) and D), and decide which is the best answer. Then mark the corresponding letter on the Answer Sheet with a single line through the center. What is the probable relationship between the two speakers（）
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