在GIS的开发设计中，将逻辑模型转化为物理模型的这个阶段是（）
A.系统分析
B.系统设计
C.系统实施
D.系统维护
参考答案：C
— If the traffic hadn't been so heavy, I could have been back by 6 o'clock.
— What a pity! Tina ________ here to see you. [ ]
A. is
B. was
C. would be
D. has been
集中器和终端连续（）天掉线、电能表数据采集连续（）天未成功或表码异常，应派发现场维护工单。
