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【简答题】
设关系模式 R(ABCD) , F 是 R 上成立的 FD 集, F={A → B , C → B} ,则相对于 F ,试写出关系模式 R 的候选键。并说明理由。
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A.
供应链也是一条价值链，价值链也是供应链。
B.
价值链是比供应链更大的一个理论体系。
C.
价值链是实施供应链管理的前提。
D.
价值链和供应链都是一种战术运作方法。
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【单选题】Some scientists believe that brain is pre-programmed for language. The word 'pre programmed' means_______.
A.
programmed already
B.
programmed before one is born
C.
programmed early
D.
programmed by women
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【多选题】不宜久煎的药物有
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薄荷
B.
苍耳子
C.
羌活
D.
葛根
E.
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【单选题】听力原文：M: There is going to be a bus strike tomorrow. W: It will be all right if it is a fine day, but if it is wet there will be long queues on the underground. What does the woman worry about most?
A.
Bad weather.
B.
Bus strike.
C.
Heavy traffic.
D.
Too many people.
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【单选题】Some scientists believe that the brain is pre-programmed for language. Here 'pre-programmed' means ______.
A.
programmed already
B.
programmed before one is born
C.
programmed early
D.
programmed by women
查看完整题目与答案
【单选题】宗教改革的领袖们以及最初开出了宗教改革的潮流带有()色彩。
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B.
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C.
等级主义
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【单选题】听力原文：M: How was the trip, Ellen? W: It was all right, only the plane should have taken off at 14:00, but it was grounded for two hours and fifteen minutes because of bad weather. Q: When did the plane...
A.
At 6:15.
B.
At 5:50.
C.
At 16:05.
D.
At 16:15.
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【单选题】听力原文：W: Sorry, I'm late, James. M: It's all right, Mary. Where have you been? W: At the police station. M: Where? W: At the police station. I've lost my briefcase. M: Oh, no! What happened? Was there ...
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B.
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D.
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【判断题】知识发现的原始数据,可以是结构化的,如数据库中的数据; 也可以是半结构化的,如文本、图形和图像数据;但不能是异构型数据()
A.
正确
B.
错误
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【判断题】惯性冲击静电除尘器是利用惯性力和电场力作用,将极板与气流方向垂直设置,提高气速可提高除尘效率。
A.
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B.
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相关题目：
【单选题】以下哪个是供应链与价值链关系的正确描述
A.
供应链也是一条价值链，价值链也是供应链。
B.
价值链是比供应链更大的一个理论体系。
C.
价值链是实施供应链管理的前提。
D.
价值链和供应链都是一种战术运作方法。
查看完整题目与答案
【单选题】Some scientists believe that brain is pre-programmed for language. The word 'pre programmed' means_______.
A.
programmed already
B.
programmed before one is born
C.
programmed early
D.
programmed by women
查看完整题目与答案
【多选题】不宜久煎的药物有
A.
薄荷
B.
苍耳子
C.
羌活
D.
葛根
E.
紫苏
查看完整题目与答案
【单选题】听力原文：M: There is going to be a bus strike tomorrow. W: It will be all right if it is a fine day, but if it is wet there will be long queues on the underground. What does the woman worry about most?
A.
Bad weather.
B.
Bus strike.
C.
Heavy traffic.
D.
Too many people.
查看完整题目与答案
【单选题】Some scientists believe that the brain is pre-programmed for language. Here 'pre-programmed' means ______.
A.
programmed already
B.
programmed before one is born
C.
programmed early
D.
programmed by women
查看完整题目与答案
【单选题】宗教改革的领袖们以及最初开出了宗教改革的潮流带有()色彩。
A.
精英主义
B.
资本主义
C.
等级主义
D.
军国主义
查看完整题目与答案
【单选题】听力原文：M: How was the trip, Ellen? W: It was all right, only the plane should have taken off at 14:00, but it was grounded for two hours and fifteen minutes because of bad weather. Q: When did the plane...
A.
At 6:15.
B.
At 5:50.
C.
At 16:05.
D.
At 16:15.
查看完整题目与答案
【单选题】听力原文：W: Sorry, I'm late, James. M: It's all right, Mary. Where have you been? W: At the police station. M: Where? W: At the police station. I've lost my briefcase. M: Oh, no! What happened? Was there ...
A.
Her cheque book.
B.
Her papers for work.
C.
Her laptop.
D.
Her appointment book.
查看完整题目与答案
【判断题】知识发现的原始数据,可以是结构化的,如数据库中的数据; 也可以是半结构化的,如文本、图形和图像数据;但不能是异构型数据()
A.
正确
B.
错误
查看完整题目与答案
【判断题】惯性冲击静电除尘器是利用惯性力和电场力作用,将极板与气流方向垂直设置,提高气速可提高除尘效率。
A.
正确
B.
错误
查看完整题目与答案