The graph of f'' is given in the figure below.




(Click on the graph for a larger version.)
Draw graphs of f and f', assuming both go through the origin, and use them to complete the following statements (enter the x-values as x1, x2, etc.):


A. f(x) is greatest at x =


B. f(x) is least at x =


C. f'(x) is greatest at x =


D. f'(x) is least at x =


E. f''(x) is greatest at x =


F. f''(x) is least at x =