A single reflection, like shouting at the side of a mountain and hearing
your voice come back to you, is an 'echo'.
Multiple reflection, like clapping your hands once inside a large room,
is 'reverberation'.
If f=140hz
speed=?
wavelength=?
without all information given, it would be difficult to answer but the formula is speed=frequency ×wavelength
The force that opposes motion to moving parts is F<span>riction</span><span>
Hope this helped!
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Yes,and because not everyone can wink and often that someone can only wink with one eye only