Part 2/2 please.The answer to Part 1/2 is 4.5 m

In order to calculate the wave speed, we can use the formula below:
[tex]v=\lambda f[/tex]Where lambda is the wavelength and f is the frequency.
If the wavelength is 4.5 meters and the frequency is 3 Hz, the speed is:
[tex]v=4.5\cdot3=13.5\text{ m/s}[/tex]