Use the graph of f to identify the critical numbers of f identify the open intervals on which f is increasing or decreasing and determine whether f has a relative maximum a relative minimum or neither at each critical number If an answer does not exist enter DNE a y X 2 2 decreasing 6 2 i Identify the critical numbers of f Enter your answers as a comma separated list 4 X ii Identify the open interval s on which f is increasing or decreasing Enter your answer using interval notation increasing relative maximum X iii Determine whether f has a relative maximum a relative minimum or neither at each critical number Enter your answers as a comma separated list relative minimum X