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Planetary system.
Every 10.0 seconds, a crest of the wave passes the pier. This means that the period of the wave is exactly 10.0 s:

which means that the frequency of the wave is

The wavelength of a wave is related to its frequency by the relationship

where v is the speed of the wave.
In this problem, v=5.6 m/s; if we use the previous formula, we find the wavelength of the wave:
Answer:
<h2>Solving elastic collisions problem the hard way</h2><h3 />
Explanation:
perfect drawing