【多选题】If pilots cannot establish normal radiotelephonycommunication on current frequency, the pilots should ( ).
A.
change frequency as soon as possible.
B.
contact with other pilots or controllers.
C.
monitor the frequency.
D.
standby the frequency.
【判断题】( )当运行中的变压器油色变化过快,油内出现碳质等,应立即将变压器停运,并进行处理。
【简答题】Radar helps pilots to ______
【单选题】以下( ) 不是计算机网络常采用的基本拓朴结构
【单选题】关于肩关节离断,哪项不正确
B.
圆的肩关节有利于假肢接受腔的适配,悬吊,和稳定