The abandon ship signal sounded by the vessels whistle is （）.
By how much is a signal’s strength reduced when the signal passes through an object thatintroduces 3 dB of attenuation？（）
If you hear more than six short blasts and one long blast of the whistle supplemented by the same signal on the general alarm，you should（）.
A whistle signal of one prolonged，one short，one prolonged and one short blast，is sounded by a vessel（）.
When you are firing a pyrotechnic distress signal，it should be aimed（）.
While reading the muster list, you see that "three short blasts on the ships whistle and the same signal on the general alarm bells" is the signal for （）.
When analog signals are digitized using the G.711 codec， voice samples are encapsulated into protocol data units （PDUs） involving which three headers？ （）
The emergency signal for fires is sounded on the ship’s whistle and general alarm as（）.
When a router converts analog signals to digital signals， what three steps are always included in the process？（）
When you are firing a pyrotechnic distress signal，it should be aimed at（）.
While underway，in fog，you hear a whistle signal of one prolonged blast followed by two short blasts. This signal is sounded by a vessel（）.
In the emergency alarm signals, if the alarm or whistle two long sounds followed by one short sound for 1 minute, it is the （） emergency.
While working in the engine room, you hear seven short blasts followed by one long blast on the ships whistle, supplemented by the same signal on the general alarm bellsYou should （）.
When you hear three short blasts on the ships whistle and the same signal on the general alarm bells, you （）.
What are two steps that are taken when a router converts a voice signal from analog to digital form？（）
If you hear more than six short blasts and one long blast of the whistle supplemented by the same signal on the general alarm,you should（）.
All of the following are distress signals EXCEPT（）.
When a vessel signals her distress by means of a gun or other explosive signal，the firing should be at intervals of approximately（）.
When a router converts analog signals to digital signals， what three steps are always included in the process？ （）
When two vessels are in sight of one another and NOT in or near an area of restricted visibility，any of the following signals may be given EXCEPT（）.
Analog signal and digital signal are two kinds of signals in the form of control.
Hand signals are not involved into cultural awareness.
When Mr Williams heard the police whistle_____.
