1. The figure below shows the graph of f the derivative of the function f, on the closed interval from x = -2 to x = 6. The graph of the derivative has horizontal tangent lines at x = 2 and x = 4.
(2,-J)
Find the x-value where f attains its absolute minimum value on the closed interval from x = -2 to x = 6. Justify your answer. (10 points)