Antonio's toy boat is bobbing in the water under a dock. The vertical distance H (in cm) between the dock and
the top of the boat's mastt seconds after its first peak is modeled by the following function. Here, t is entered in
radians.
H(t) = 5 cos(2pi/3)t)-35.5
How long does it take the toy boat to bob down from its peak to a height of -35 cm?
Round your final answer to the nearest tenth of a second.