The graph of the first derivative f' of a function fis shown. (Assume the function is defined only for 0 s x $ 9.) y = f(x) (a) On what interval(s) is f increasing? (Enter your answer using interval notation.) (b) At what value(s) of x does f have a local maximum? (Enter your answers as a comma-separated list. ) X = At what value(s) of x does f have a local minimum? (Enter your answers as a comma-separated list. ) X = (c) On what interval(s) is f concave upward? (Enter your answer using interval notation.) On what interval(s) is f concave downward? (Enter your answer using interval notation.) (d) What are the x-coordinate(s) of the inflection point of f? (Enter your answers as a comma-separated list.) X