Ключевые слова: advertisement, alert, amplification, amplifier, announce, announcement, attention, audible, audio, blank space, broadcast, broadcasting, brown background, bullhorn, call, communicate, communication, concept, control, copy space, device, electricity, electronic, emergency, equipment, loud, loudspeaker, mega, megaphone, message, phone, portable, proclaim, propaganda, public, radio, ray, shout, sound, speak, speaker, speaker phone, speech, voice, volume,