设有如下关系模式:R(A,B,C,D,E),其中R上函数依赖集为:F={(A,B)→E,E→C,C→D}。则在函数依赖的范围内该关系模式最高属于()。
A. 1NF
B. 2NF
C. 3NF
D. BCNF
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听力原文:W: I need a car this weekend, but mine has broken down.
M: I'm sorry to hear it, but you can always rent one if you have a license.
Q: What does the man mean?
(8)
A. She can use his car.
B. She can borrow someone else's car.
C. She must get her car fixed.
D. She can't borrow his car.
女性患者,25岁,有风湿性心脏病史。心悸、胸闷持续达数分钟之久,心电图示:心室率2138次/分,P波不易辨认,QRS波正常,R-R间隔绝对规整,S-T段稍下移。
对该患者下列哪项诊断可能性最大
A. 阵发性室性心动过速
B. 阵发性室上性心动过速
C. 心房颤动
D. 心室颤动
E. 窦性心动过速
A.Fix the button.B.Prepare the breakfast.C.Wait for the school bus.D.Play basketball.
A. Fix the button.
B. Prepare the breakfast.
C. Wait for the school bus.
D. Play basketball.
听力原文:W: Sarah is an American, but she has lived in Europe for most her life.
M: Yes. She speaks French and Spanish as well as English.
Q: What is Sarah's nationality?
(4)
A. French.
B. American.
C. Spanish.
D. British.