What is true about the frequency and wavelength of this sound? A:The wavelength of the sound is 0.800 m . B: The wavelength of the sound is 2.72 m . C:The frequency of the sound is 125 Hz . D:The frequency of the sound is 425 Hz .

NB: This is the complete question

A string of length 0.620 m is vibrating at 125 Hz in its second harmonic and producing sound that moves at 340 m/s .  

What is true about the frequency and wavelength of this sound?

A:The wavelength of the sound is 0.80 m .

B: The wavelength of the sound is 2.72 m .

C:The frequency of the sound is 125 Hz .

D:The frequency of the sound is 425 Hz .

Explanation:

let f1 = frequency of the first harmonic and

f2 = frequency of the second harmonic

f2 = 2f1

f1 = 125/2

f1 = 62.5 Hz

f2 = speed/ wavelength

f2 = 340/125

f2=2.72 m

when heated, the valance electrons increased their speed and transferred the heat from electron to electron.   i just took the test.

i think the answer would be reserve.