Your vessel is equipped with a fixed C0₂ system and a fire main system. In the event of an electrical fire in the engine room what is the correct procedure for fighting the fire?（）.

A.Use the C0₂ system and evacuate the engine room

B.Use the fire main system and evacuate the engine room

C.Evacuate the engine room and use the C0₂ system

D.Evacuate the engine room and use the fire main system

箭头所指的解剖结构是（）

A．砧骨

B．锤骨

C．镫骨

D．卵圆窗

E．圆窗