Consider the equation below. (If an answer does not exist, enter DNE.) f(x) = x* – 32x² + 4 (a) Find the interval on which f is increasing. (Enter your answer using interval notation.) (-4,0) U (4,00) Find the interval on which f is decreasing. (Enter your answer using interval notation.) (-0,4) U (0,4) (b) Find the local maximum and minimum values of f. local minimum value -4,4 local maximum value (c) Find the inflection points. (Order your answers from smallest to largest x, then from smallest to largest y.) (x, y) = (x, y) = Find the interval on which f is concave up. (Enter your answer using interval notation.) Find the interval on which f is concave down.(Enter your answer using interval notation.)