The answer is C. 12 meters.
The distance between the crests of an ocean is 1 wavelength. Between the first and the second crest, the distance is 1 wavelength while between the first and the third crest the difference is 2 wavelengths.
If 24 meters are 2 wavelengths, how many meters are 1 wavelength:
24m : 2w = x : 1w
⇒[tex] \frac{24m}{2w} = \frac{x}{1w} [/tex]
⇒ x = 12 meters.
