Answer:
B. 20m/s
Step-by-step explanation:
The wavelength of a wave can be calculated using the formula;
λ = v/f
Where;
λ = wavelength (m)
v = velocity (m/s)
f = frequency (Hz)
According to the information provided in this question; the wave has a wavelength (λ) of 2m and a frequency (f) of 10Hz.
Using λ = v/f
v = λ × f
v = 2 × 10
v = 20m/s.