A buoy floating in the ocean bobs up and down due to the waves. The buoy's vertical position can be modeled by the equation:

y$($t$)=(3\mathrm{.}0$cm$)$sin$[(0\mathrm{.}55$rad$/$s$)$t$]$

where y$($t$)$ is the vertical displacement of the buoy from its equilibrium position at time t$.$ What is the frequency of the buoy's bobbing motion?