Use the graph to determine the speed of the graph

Given:
It takes 1.5 s to complete one wave.
One wave covers 25 m.
To find the speed of the wave.
Explanation:
The frequency of the wave will be
[tex]\begin{gathered} f=\frac{1}{1.5} \\ =0.667\text{ Hz} \end{gathered}[/tex]The wavelength of the wave is
[tex]\lambda\text{ = 25 m}[/tex]The speed of the wave can be calculated by the formula
[tex]v=f\lambda[/tex]On substituting the values, the speed of the wave will be
[tex]\begin{gathered} v=\text{ 0.667}\times25 \\ =16.67\text{ m/s} \end{gathered}[/tex]Thus, the speed of the wave is 16.67 m/s