行动研究的特征之一是( )
A.应用发展理论B.涉及多重层C.以匿名方式填写问卷D.采用归纳一实验型设计E.20世纪70年代始用于医疗卫生领域
参考答案:A
The ( ) has several major components, including the system kernel, a memory management system, the file system manager, device drivers, and the system libraries.
A.application
B.information system
C.operating system
D.iterative
作业人员和工具与接触网必须保持()米以上的距离。
A.2
B.3
C.4
D.5