Let's be a twice-differentiable function with derivative given by f'(x) = 4x- 24x. Part A: Find the x-coordinate of any possible critical points of f. Show your work. (2 points) Part B: Find the x-coordinate of any possible inflection points of f. Show your work. (2 points) Part C: Use the Second Derivative Test to determine any relative extrema and inflection points. Justify your answers. (3 points) Part D: If f has only one critical point on the interval [5, 8], what is true about the function f on the interval [5, 8]? Justify your answers. (3 points)