往复泵启动时,泵体内()。 ["A、须充满液体","B、须排气","C、不能充满液体","D、不须充液"]
ADSL
国内负压原油稳定装置加热炉原油出口温度为()℃。 ["60~65","65~70","70~75","65~75"]
国内负压原油稳定装置螺杆式压缩机出口压力为()MPa(表压)。 ["0.5","0.4","0.3","0.2"]
TCP/IP体系结构中与ISO-OSI参考模型的1、2层对应的是哪一层() ["A、网络接口层","B、传输层","C、互联网层","D、应用层"]
FTP