SM网络中唯一识别移动台的号码是()而在公共电话交换网中唯一识别移动台的号码是()。
查看答案
1996年9月,我国成功地在北京主办了第()届国际档案大会,并成为国际档案理事会主席国。
A. 9
B. 12
C. 13
D. 14
The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by ().
A. a separate air ejector unit
B. a direct unimpeded connection between second stage and salt water feed heater
C. either by vacuum drag or an external line from the first stage via a fixed orifice
D. the fixed orifice provided in the steam supply line
发动机活塞环的开口在装配时不能与活塞销孔对正。
A. 正确
B. 错误