For the function below, find (a) the critical numbers; (b) the open intervals where the function is increasing; and (c) the open intervals where it is decreasing. f ( x ) = = 4 3 - 2x- - 288x - 24 . . . (a) Determine the critical numbers. Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. The critical number(s) is/are (Type an integer or a simplified fraction. Use a comma to separate answers as needed.) O B. There are no critical numbers. (b) On which intervals is the function increasing? Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. Increasing on (Type your answer in interval notation. Simplify your answer. Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.) O B. Never increasing (c) On which intervals is the function decreasing? Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. Decreasing on (Type your answer in interval notation. Simplify your answer. Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.) O B. Never decreasing