水套炉液位计投运时，应先关（）。
A、放空阀
B、排污阀
C、上流阀
D、下流阀
参考答案：A
按照如图所给实验器材，设计一个测量小灯泡电阻的实验．且要求滑片P向A端移时，电流表的示数变小．连接实物图并画出相应的电路图．
— Excuse me, do you know _____?
— I'm sorry. I am new here. [ ]
A. where is the nearest bus station
B. where the nearest bus station is
C. where the nearest bus station was
