Answer:
0.2 Hz
Explanation:
The frequency of a wave is given by
[tex]f=\frac{v}{\lambda}[/tex]
where
f is the frequency
v is the speed of the wave
[tex]\lambda[/tex] is the wavelength
For the ocean waves in this problem,
[tex]\lambda=15 m[/tex] is the wavelength
v = 3 m/s is the speed
So their frequency is
[tex]f=\frac{3 m/s}{15 m}=0.2 Hz[/tex]