Tuenuly me open intervals on which the graph of the luncoon is concave upward of concave downward. Assume that the graph extends past what is shown. 107 18- 4- -10 -8 -6 -4 -20 2- 6 8 10 -2- 4- 6- Note: Use the letter U for union. To enter oo, type infinity. Enter your answers to the nearest integer. If the function is never concave upward or concave downward, enter NA in the associated response area. concave upward: concave downward