Question 963349
 At 20 degrees C, the speed of sound is approximately 344 m/s.
 The lower limit of sound waves audible to the human ear is about 0.0172 m.
 What is the frequency of these sound waves?
:
Wave-length = velocity/frequency
.0172f = 344
f = 344/.0172
f = 20,000 or about 20 kc, that's the upper limit of the human ear