Hey guys, I'm kinda having some problem with this question on finding the frequency of the sound wave of the picture provided. The speed the sound wave is travelling at is 340m/s. I know that in order to find the frequency, I hve to tke speed / wavelength. However, I'm not sure how to find the wavelength. Btw, b, d, and f represent the centre line in the three lines representing the compression. I've tried searching on identifying wavelengths, but wht I've found is that the wavelength should be 2m / 2 since line b should represent a point on the x-axis before the graph reaches a trough and goes back up to the x-axis, which should be represented by c, reaches a peak and finally reaches the x-axis again, which is represented by d. Therefore, b to d should be one wavelength, which equals to 1m. It's quite confusing to explain it this way, but I hope you guys can get it. Thanks and any help is greatly appreciated.