I need help with this four problem please explain

Find the equation of the tangent line to the curve y = 6 sin a: at the point (g, 3). The equation of this tangent line can be written in the form y = mm + b where dy If y = (t + 2t + 6) (2t2 + 5), find dt dy = dtFind the derivative of: 6 sin (9x4) . Hint: sin (x) = [sin(a)] ...so use the chain rule (twice!).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) = 3cos(%t + 7%) + 5 where t is the number of hours after midnight. Find the rate at which the depth is changing at 1 am. Round your answer to 4 decimal places