Find the derivative of the function f(x) = 3x + 8 at number 14. (Use symbolic notation and fractions where needed.) f' (14) =As an object in rectilinear motion moves, its distance s from the origin at time to is given by the equation s = s(t) = 11+2 - 3, where's is in centimeters and t is in seconds. Find the velocity u at to = 5. (Use decimal notation. Give your answer to two decimal places.) U(5) = cm/s Find the velocity at to = 7. (Use decimal notation. Give your answer to three decimal places.) U(7) = cm/s