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问题 单项选择题

在Visual FoxPro中，嵌套查询是基于( )的查询

A．2个关系

B．3个关系

C．多个关系

D．2个或3个关系

答案

参考答案：C

解析： 在Visual FoxPro中，嵌套查询是基于多个关系的查询。这类查询所要求的结果出自一个关系，但相关的条件却涉及多个关系。

多项选择题

已知：

并设h=20%，r＝60%，t＝4%，s＝50%，e＝14%根据上述资料回答下列问题(保留两位小数)。

为扩大内需，中央银行利用差别利率政策，使r降为5%，s变为40%，e变为10%，这样，K1、K2、K3分别改变为（）

A．0.545

B．0.60

C．3.28

D．4.37
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问答题

Read the argument and the instructions that follow it, and then make any notes that will help you plan your response. Write your response on a separate sheet of paper. If possible, type your essay on a word processor.
A spokesman for a dairy company issued the following statement:
Many consumers buy organic milk because they are concerned about the consequences of the widespread use of recombinant bovine growth hormone and antibiotics in the conventional dairy industry. These concerns, however, are unfounded. While bovine growth hormone has been shown to produce significant developmental effects in cattle, no study has ever shown that its presence in commercial milk has had any developmental effects on human consumers. Regarding antibiotics, while it has been argued that large-scale, preemptive use of antibiotics in cattle feed can interfere with the animals’ immune systems and can lead to the proliferation of antibiotic-resistant strains of bacteria, neither of these effects affect the quality of the milk produced by cattle that are fed antibiotics. Therefore, there is no reasonable justification for a consumer to pay $5 for a gallon of organic milk when a perfectly good gallon of conventional milk can be had for half the price.
Discuss how well reasoned you find this argument. In your discussion, be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative examples or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.
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