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【单选题】
(2分) 在关系型数据库中,参照完整性是通过()来实现的。A.
唯一约束
B.
主键约束
C.
默认值约束
D.
外键约束
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【单选题】机车过充压力消除是电空制动控制器手柄由“过充位”回“运转位”后,制动管过充压力是经( )排出。过充消除的时间需要120s。
A.
紧急阀
B.
中继阀
C.
分配阀
D.
以上都不是
【单选题】回答题 Explore Jordan Wadi Rum is the name given to a valley cut into the sandstone and hard rock in southwest Jordan. _____（46）The name Rum most likely comes from an Aramaic word meaning 'high' or 'elev...
A.
It is the second highest peak in Jordan， rising directly above the Rum valley opposite Jebal Urn Ishrin.
B.
This vast stretch of water receives a number of incoming rivers， including the River Jordan.
C.
The area has been used as a background setting in a number of films.
D.
It is the largest wadi （riverbed） in Jordan.
E.
Every day seven million tons of water evaporate from the lake， but the minerals remain， causing the salt content to increase.
F.
It is without doubt Jordan's most valuable treasure.
【单选题】二．单项选择： 1.It is hard to imagine smells _____ when a film is shown in the future.
A.
are given away
B.
are put away
C.
are sent out
D.
are given out
【单选题】Madam Curie, ____ life had once been very hard, was given two Noble Prizes. [ ]
A.
of whom
B.
for whom
C.
for whose
D.
in whom
【单选题】Albert Einstein, ____ life had once been very hard, was given the Nobel Prize for physics in 1921. [ ]
A.
of whom
B.
for whom
C.
for whose
D.
in whom
【单选题】机车过充压力消除是电空制动控制器手柄由“过充位”回“( )”后,制动管过充压力是经中继阀排出。过充消除的时间需要120s。
A.
中立位
B.
制动位
C.
运转位
D.
以上都不是
【单选题】It is hard to imagine smells _____ when a film is shown in the future. [ ]
A.
are given away
B.
are put away
C.
are sent out
D.
are given out
【单选题】Madam Curie, ________life had once been very hard, was given two Nobel Prizes. [ ]
A.
of whom
B.
for whom
C.
for whose
D.
in whom
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