APU燃油泵的压力电门的作用是（）. ["低压指示","控制APU燃油泵","关闭APU低压活门","A+B"]
1770—KF2面板（）时表示内存、定时器等自诊断出故障 ["A、ACTV状态指示灯闪亮","B、ACTV状态指示灯灭","C、CPU状态指示灯亮","D、CPU状态指示灯闪亮"]
熟石膏由天然的石膏经（）低温煅烧分解成半水石膏。 ["37~80度","57~120度","107~190度","200~250度"]
1770—KF2面板（）时表示接线有误，必须检查 ["A、ACTV状态指示灯闪亮","B、ACTV状态指示灯灭","C、CPU状态指示灯亮","D、CPU状态指示灯闪亮"]
木质基层涂刷清漆，木质基层上的节疤，松脂部分应用（）封闭。 ["油性腻子","虫胶漆","原子灰","石膏腻子"]
什么是天线增益？
