Answer:
20 m/s
Explanation:
The speed of a wave is given by:
[tex]v=\lambda f[/tex]
where
[tex]\lambda[/tex] is the wavelength
f is the frequency
v is the speed
For the wave in this problem,
f = 10 Hz is the frequency
[tex]\lambda=2 m[/tex] is the wavelength
So the speed is
[tex]v=(10 Hz)(2 m)=20 m/s[/tex]