下列开关中,()启动能引起反萃苯己液进料调节阀立即关闭。
A、苯泵槽高液位开关
B、苯蒸馏蒸汽低流量开关
C、苯汽提蒸汽低流量开关
D、硫铵汽提塔高压开关
参考答案:A, D
How did it that the car fell off the bridge into the river? [ ]
A. come out
B. come about
C. come across
D. come up
转向垂臂与转向垂臂(摇臂)轴,若无装复对正标记,如何确定其正确装复位置?