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The sound file is 31 s. The tone frequencies are 400, 300 and 500 Hz. The period time is 2.4 s and the time of each tone is 0.8 s. Extension of sound file: .mp3 An automatic return will occur |
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The sound file is 31 s. The tone frequencies are 400, 300 and 500 Hz. The period time is 2.4 s and the time of each tone is 0.8 s. Extension of sound file: .mp3 An automatic return will occur |