在夹具中,长圆柱心轴,作工件定位元件,可限制工件的()自由度。
A.三个
B.四个
C.五个
参考答案:B
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①会造成未成年人精神萎靡、纪律涣散 ②一定会让未成年人走上犯罪道路 ③会使未成年人不思进取 ④极易诱发未成年人性犯罪和相关的暴力犯罪
A.①②③④
B.①②
C.①③④
D.③④
The relational database model requires the data be (110) through programs that don’t rely on the position of the data in the database. This is in direct (111) to the other database mode, where the program has to follow a series of pointers to the data it seeks. A program (112) a relational database simply asks for the data it seeks; the DBMS performs the necessary searches and (113) the information. The (114) on how the search is done are specific to the DBMS and vary from product to product.
(114)是()
A.details
B.documents
C.tails
D.tenants