塔设备按塔内件结构可分为()。 ["A、板式塔","B、舌型塔","C、填料塔","D、泡罩塔"]
IPX默认使用的路由协议是() ["A、静态路由协议","B、RIP","C、IGRP","D、OSPF"]
泄漏氨的原因有()。 ["连接法兰松动","填料松动","操作不当","焊缝被腐蚀"]
在向Quidway路由器发送升级程序时,应选用的协议是() ["A、Xmodem","B、Ymodem","C、Zmodem","D、Ymodem-G"]
稀硝酸装置中利用低压蒸汽加热的设备有()。 ["氨蒸发器","氨辅助蒸发器","氨过热器","汽包"]
运输收入事故分为几类?