正确答案: A

90%的人都认识失业者的事实并不表明失业率高到不可被接受。

题目：基于以下题干：张小珍：在我国，90%的人所认识的人中都有失业者，这真是个令人震惊的事实。王大为：我不认为您所说的现象有令人震惊之处。其实，就5%这样可接受的失业率来讲，每20个人中就有1个人失业。在这种情况下，如果一个人所认识的人超过50个，那么，其中就很可能有1个或更多的失业者。根据王大为的断定能得出以下哪个结论?

解析：解析：根据王大为所说的可作出以下几个断定：

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举一反三的答案和解析：

[单选题]One of the difficulties in building an SQL,like query language for the Web is the absence of a database(71) for this huge, heterogeneous repository of information. However, if we are interested in HTML documents only, we can construct a virtual schema from the implicit structure of these files. Thus, at the highest level of(72) , every such document is identified by its Uniform. Resource Locator(URL), has a(73) and a text. Also, Web servers provide some additional information such as the type, length, and the last modification date of a document. So, for data mining purposes, we can consider the set of all HTML documents as a relation:Document(url, title, text, type, length, modif)Where all the(74) are character strings. In this framework, an individual document is identified with a(75) in this relation. Of course, if some optional information is missing from the HTML document, the associate fields will be left blank, but this is not uncommon in any database.

schema

[多选题]____

图像序列变化的程度

[单选题]内存地址从0AC000H到0C7FFFH，共有(1)K个地址单元，如果该内存地址按字(16bit)编址，由28片存储器芯片构成。已知构成此内存的芯片每片有16K个存储单元，则该芯片每个存储单元存储(2)位。(1)

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