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【单选题】
在关系模式中,对应关系的主键是指__________。A.
第一个主键或属性组
B.
能唯一确定的一组属性
C.
不能为空值的一组属性
D.
不能为外键的一组属性
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
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【简答题】首次提出生态学定义的科学家是()
【单选题】纤溶系统亢进引起的出血宜选用 prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
A.
维生素K
B.
鱼精蛋白
C.
右旋糖酐
D.
氨甲苯酸
E.
华法林
【单选题】听力原文：M: Hurry, there is a bus coming. W: Why run? There will be another one in two or three minutes. Q: What does the woman mean? (14)
A.
The next bus is coming soon.
B.
The bus will wait a few minutes at the stop.
C.
There are only two or three passengers waiting for the bus.
D.
They can catch this bus without running.
【单选题】Unless there is danger of further injury，a person with a compound fracture should not be moved until bleeding is controlled and ().
A.
The bone has been set
B.
The fracture is immobilized
C.
Radio advice has been obtained
D.
The wound has been washed
【单选题】听力原文：W: I've just heard there are going to be showers on and-off all weekend. M: There goes the picnic. Q: What does the man mean? (17)
A.
The picnic will probably be cancelled.
B.
He's glad that the picnic is in this weekend.
C.
It's not going to rain.
D.
He knows where to hold picnic.
【单选题】—______the woman there be our English teacher? —She______ be, but I' m not sure.
A.
May... mustn't
B.
Can... may
C.
Can... can't
D.
Must... needn't
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