设有关系模式S(Sno，Sname，Pno，Pname，Q，A)表示销售员销售商品情况，其中各属性的含义是：Sno为销售员员工号，Sname为销售员姓名，Pno为商品号，Pname为商品名称，Q为销售商品数目，A为销售商品总金额。根据定义有如下函数依赖集：P=Sno→Sname，Sno→Q，Sno→A，Pno→Pname。
关系模式S的关键字是 (46) ，W的规范化程度最高达到 (47) 。若将关系模式 S分解为3个关系模式S1(Sno，Sname，Q，A)，S2(Sno，Pno，Pname)，则S1的规范化程度最高达到 (48) ，S2的规范化程度最高达到 (49) 。
SQL中集合成员资格的比较操作“元组IN(集合)”中的“IN”与 (50) 操作符等价。
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When to Take Medicine Is Important{{/B}} Our bodies are wonderfully skillful at maintaining balance. When the temperature jumps, we sweat to cool down. When our blood pressure falls, our hearts pound to compensate. As it turns out, though, our natural state is not a steady one. Researchers are finding that everything from blood pressure to brain function varies rhythmically with the cycles of sun, moon and seasons. And their insights are yielding new strategies for keeping away such common killers as heart disease and cancer. Only one doctor in 20 has a good knowledge of the growing field of "chronotherapeutics", the strategic use of time (chronos) in medicine. But according to a new American Medical Association poll, three out of four are eager to change that. "That field is exploding," says Michael Smolensky. A. heart disease and cancer are the most common killers of human being B. blood pressure and brain function are decided by cycles of sun, moon and seasons C. the functions of human bodies have much to do with nature D. any change in human bodies goes systematically with changes in the environment [单选题]辙叉心宽40 mm断面处，辙叉心垂直磨耗（不含翼轨加高部分），50 kg/m及以下钢轨，在正线上超过（ ）mm为高锰钢整铸辙叉轻伤标准。
A.2 B.4 C.6 D.8 E.10 F.12 [填空题]在数据库镜像的两种模式中，两台主机均为工作机，并为信息系统提供支持的是______。一台主机为工作机，另一台为备份机的是______。
[判断题]汽车驾驶员可以在开车时使用手机.（ ）
A.正确 B.错误 [单项选择]在宏的表达式中还可能引用到窗体或报表上控件的值。引用窗体控件的值可以用表达式______。
A. Forms!窗体名!控件名 B. Forms!控件名 C. Forms!窗体名 D. 窗体名!控件名 [单选题]
(2分) 煤的磨损性以冲刷磨损指数Ke表示，Ke值大小与煤的磨损程度关系错误的是（ ）。 A.Ke＜1.0轻微 B.Ke＝1.0～2.0不强 C.Ke＝2.0～3.5强 D.Ke＝3.5～5.0很强 [单项选择]钢筋焊接方法有( )。
A. 闪光对焊、电弧焊、电渣压力焊和电阻点焊 B. 闪光对焊、电弧焊和电渣压力焊 C. 电弧焊和电渣压力焊 D. 电渣压力焊和电阻点焊 我来回答: 提交
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