有功电能表准确度等级有（）。
A、0.2S
B、0.5S
C、1.0S
D、2.0S
参考答案：A, B, C, D
---- I ________ your advice very much.
---- You are welcome. I hope it is ________ to you.
A．like; unhelpful
B．raise; unhopeful
C．appreciate; helpful
D．thank; hopeful
设备升级完成后一般会进行哪些后续操作？
