在空袭预警系统中,鸣6秒、停6秒的连续急促短音,反复15遍的是()。
A、预先警报
B、空袭警报
C、解除警报
D、防空警报
A、预先警报
B、空袭警报
C、解除警报
D、防空警报
A、间断鸣三次长声,即鸣30s、停、鸣30s、停、鸣30s B、间断鸣一长、一短三次,即鸣20s、鸣10s、停、鸣20s、鸣10s、停、鸣20s、鸣10s C、连续三短声,即鸣10s、停、鸣10s、停、鸣10s D、一次长声,鸣60s
A、间断鸣三次长声,即鸣30s、停、鸣30s、停、鸣30s B、间断鸣一长、一短三次,即鸣20s、鸣10s、停、鸣20s、鸣10s、停、鸣20s、鸣10s C、连续三短声,即鸣10s、停、鸣10s、停、鸣10s D、一次长声,鸣60s
A、间断鸣三次长声,即鸣30s、停、鸣30s、停、鸣30s B、间断鸣一长、一短三次,即鸣20s、鸣10s、停、鸣20s、鸣10s、停、鸣20s、鸣10s C、连续三短声,即鸣10s、停、鸣10s、停、鸣10s D、一次长声,鸣60s
A、A.间断鸣三次长声,即鸣30s、停、鸣30s、停、鸣30s B、B.间断鸣一长、一短三次,即鸣20s、鸣10s、停、鸣20s、鸣10s、停、鸣20s、鸣10s C、C.连续三短声,即鸣10s、停、鸣10s、停、鸣10s D、D.一次长声,鸣60s