Note: If you are asked for value(s), give your answer as a single value (e.g. 17), or a comma separated list (e.g. 1,2,3), or NONE. If you are asked for an interval, give your answer in interval notation. Type INF for oo and -INF for -0. () Let which has the following derivatives: f'(x) = 2xe" + (x-4)e", f" (x)=2e" + 2xe" + 2xe" + (x - 4)e". (a) Find the locations (the x-values) of the points of inflection. B= (b) Determine the -intervals on which f is concave up or down. f(x) = (x-4)e*, The left-most interval is and on this interval f is ? The middle interval is and on this interval fis ? The right-most interval is and on this interval f? Concave Down