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Suppose that the graph below is the graph of f'(x), the derivative of a function f(x). Find the open a) List any open interval(s) on which f(x) is increasing. Select the correct choice intervals where f(x) is a) increasing, or b) decreasing. below and, if necessary, fill in the answer box to complete your choice. O A. (Type your answer in interval notation. Use a comma to separate answers as needed.) O B. The function f(x) is never increasing. b) List any open interval(s) on which f(x) is decreasing. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. (Type your answer in interval notation. Use a comma to separate answers as needed.) O B. The function f(x) is never decreasing