how do I measure the wavelength/amplitude

Answer:
The wavelength can always be determined by measuring the distance between any two corresponding points on adjacent waves. In the case of a longitudinal wave, a wavelength measurement is made by measuring the distance from a compression to the next compression or from a rarefaction to the next rarefaction.
Explanation:
Thank me later
Answer:
Explanation:
So what you want to do is measure the wavelength for the wavelength by putting the ruler under or above the distance (show in picture).
amplitude you want to measure it inside of the wave. so when measuring move the ruler sideways.
( i hope this makes sense)