乙二醇脱水塔停车检修时,首先用()置换。
A、工厂风
B、仪表风
C、氮气
D、水蒸汽
参考答案:C
_____ is your new pencil case? It's 13 yuan. [ ]
A. How old
B. How many
C. How much
重点化验检查的项目应是
A.尿常规
B.血常规
C.肝功能
D.肾功能
E.眼晶状体