能实现（）的工艺装备为机床夹具。 A.工件的定位 B.工件的夹紧 C.工件的定位与夹

小桅同学在实验室里将一金属块放在酒精灯上加热了一段时间，此时金属块的密度将_____ （选填“变大”、“变小”或“不变”）．

One of my teammates fell ill _______ he can't practice with us now. [ ]

A. so that

B. however

C. instead of

D. never mind

当以太网检测到冲突时，会发出一个（）。

A、冲突包；

B、令牌包；

C、扩展阻塞包；

D、冲突阻塞包。

A 16-year-old girl comes to the school nurse complaining of cramps, backache, and nausea with her periods. The nurse most likely would interpret these symptoms as which of the following

A．Pathologic.

B．Physiologic.

C．Psychogenic.

D．Psychosomatic.

屈曲型肱骨髁上骨折手法复位成功后，一般采用外固定将肘关节固定在（）

A.肘关节伸直位

B.肘关节屈曲90°位

C.肘关节屈曲60°左右位

D.肘关节屈曲40°左右位

E.肘关节极度屈曲位