在基于构件的开发方法中，信息系统的构件主要包括：接口、实现和
A．功能
B．代码
C．文件
D．部署
参考答案：D
______ of money spent on the bridge. [ ]
A. A large amount ; were
B. Large amounts; were
C. Large amount; was
D. A plenty; was
下列不属于空压机最重要且经常需要维护的易损件是（）。
A、空气滤器
B、安全阀
C、联轴节
D、轴承
