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【简答题】
数据库系统中常用的三种数据模型有层次模型、 _________ 和关系模型
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【简答题】Plastics are considered one of the most serious pollutants causing environmental problems. The garbage containing plastics end up in the waterways that ually flow into the oceans. Accumulation (聚...
【简答题】数据链路层的协议数据单元是。
【单选题】下列关于培训说法错误的是( )
A.
药企中只有关键人员才需要培训
B.
高学历人才上岗也需要岗前培训
C.
主要管理培训部门是人力资源部门
D.
培训内容是一般根据培训对象和培训需求制定的
【单选题】_________ his membership card, Tim decided to make a phone call to check whether there was something wrong.
A.
Not having received
B.
Not to receive
C.
Not received
D.
Having not received
【单选题】______ are chiefly derived from petroleum.
A.
Plastics today
B.
There are plastics today
C.
Because today plastics today
D.
Due to plastics today
【单选题】What arrangements did Tim make for accommodation?
A.
He bought an expensive house .
B.
He stayed in a company flat.
C.
He arranged to move in with a colleague .
相关题目：
【单选题】下列关于培训说法错误的是( )
A.
药企中只有关键人员才需要培训
B.
高学历人才上岗也需要岗前培训
C.
主要管理培训部门是人力资源部门
D.
培训内容是一般根据培训对象和培训需求制定的