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【简答题】
设 F 是基本关系 R 的一个或一组属性,但不是关系 R 的码,如果 F 与基本关系 S 的主码 Ks 相对应,则 F 是 R 的( ),基本关系 R 称为( ),基本关系 S 称为( )。(请填写字母) A. 主码 B .外码 C .参照关系 D .被参照关系或目标关系
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皮皮学刷刷变学霸
举一反三
【单选题】— I wonder if I ______ late for class, Mr. Li?— Ben, you are late again.
A.
have been
B.
am
C.
was
【单选题】About ovary, which of the following is false?
A.
only one ovarian follicle maturate during every menses cycle
B.
corpus luteum secretes estrogen and progesterone after ovulation
C.
if ovum isn ’ t fertilized, corpus luteum regresses to corpus albicans.
D.
the amount of ovarian follicles in ovary is determined by newborn phase in human
E.
the endocrine regulation of ovulation is emergence of peak of blood LH/FSH before ovulation.
【单选题】—Ben, would you like to play football with us? —______ , but I have to wash the dishes (洗盘子) first. [ ]
A.
No, I can't
B.
I don't want to
C.
Yes, please
D.
I'd love to
【单选题】- Ben, can you come to play football with us now? - ________, but I have to wash the dishes first.
A.
No, I can’t
B.
I don’t want to
C.
Yes, please.
D.
I’d love to
【简答题】有3个作业J1,J2,J3,其运行时间分别是2, 6, 4小时,假设它们同时到达系统,并在同一处理器上以单道方式运行,则平均周转时间最小的执行序列是( )、( )、( )。
【简答题】听对话，填空。 A: ___________! Tom! B: Hi! Ben! A: Do you have a ___________? B: Yes, I have. A: Where is it? B: It's ___________ the ___________. A: Is it ___________? B: Yes, it is. A: Who ___________ it t...
【单选题】— Ben, Would you like to play football with us? — , but I have to wash the dishes first [ ]
A.
No, I can't
B.
I don't want to
C.
Yes, please
D.
I'd love to
【单选题】______, as long as I’m with nature, I don’t care.
A.
However tough is the journey
B.
Whatever tough is the journey
C.
However tough the journey is
D.
Whatever tough the journey is
【单选题】He promised to pick me up at the school gate. However, he yet.
A.
hasn’t arrive
B.
didn’t arrive
C.
doesn’t arrive
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