Question 5 (2 points) Consider the function f(x) - x4 - 3x | 3x- 1. Which of the following statement is/are true? I) The graph of y=f(x) is concave up on (-1, 1), and is concave down on (3, 4). II) The graph of y=f(x) is concave down on (-1, 1), and is concave up on (3, 4). Ill) The graph of y=f(x) is concave down on (-5, -3), and is concave up on (3, 5). IV) The graph of y=f(x) is concave up on (-6, -5), and is concave down on (5, 6). 1, HI, III, IV None of the provided answers None of them is true Oil, IV