LIST Next Problem (1 point) Let f(x) = 6 - 7x. At what x-values is f'(x) zero or undefined? X = (If there is more than one such x-value, enter a comma-separated list; if there are no such x-values, enter "none".) On what interval(s) is f(x) increasing? f(x) is increasing for x in (If there is more than one such interval, separate them with "U". If there is no such interval, enter "none".) On what interval(s) is f(x) decreasing? f(x) is decreasing for x in (If there is more than one such interval, separate them with "U". If there is no such interval, enter "none".) Note: You can earn partial credit on this