单项选择题
A.an air leak has developed in the tank
B.the tank cooling system has malfunctioned
C.the pilot cylinder discharge valve is leaking
D.an excessive amount of insulation has been installed on the tank and piping
单项选择题 A crew member is having an epileptic convulsion. You should（）.
单项选择题 A crew member has suffered frostbite to the toes of the right foot. Which is NOT an acceptable first aid measure?（）
单项选择题 A copy of the Articles of Agreement，less the signatures，is required to be posted. This document is called the（）.