压缩机润滑油油路系统的储压器应充氮气到规定压力并保持()小时检查无泄漏。
A.6
B.12
C.24
D.48
参考答案:B
Look and choose. (根据图片,选择正确的答案)
1. The _____ has a long tail. [ ]
A. monkey
B. squirrel
2. Make yourself _____. [ ]
A. tall
B. short
3. — Where are you from?
— I'm from _____. [ ]
A. USA
B. UK
4. 一 How many _____ do you have?
— I have three. [ ]
A. pears
B. bananas
国库磁(光盘)介质档案的保管期限与相应纸介质档案的保管期限相(不)同。