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Question 19 Previous The depth (in feet) of water at a dock changes with the rise and fall of tides. The depth is modeled by the function D (t) = 5 cos at+ + A + 3 where t is the number of hours after midnight. Find the rate at which the depth is changing at 3 a.m. Round your answer to 4 decimal places. Question Help: Message instructor D Post to forum Submit