A high-frequency sonar signal (acoustic wave) is used in marine navigation to map the seabed. The graph shows how the displacement of this acoustic wave varies with distance as it travels through seawater.
a.[1]
Use the graph to determine the wavelength of the acoustic wave.
b.[3]
The speed of this acoustic wave in seawater is 1530 m/s1530\text{ m/s}1530 m/s. Calculate the frequency of the acoustic wave. Use the equation: $\text{wave speed} = \text{frequency} \times \text{wavelength}$ Give your answer in standard form and to 2 significant figures.