(1 point) Find and classify the critical points of \( f ( x ) = 3 x ^ { 8 } ( 4 - x ) ^ { 7 } \) as local maxima and minima.

Critical points: \( x = \)

Classifications:

(Enter your critical points and classifications as comma-separated lists, and enter the types in the same order as your critical points. Note that you must enter something in both blanks for either to be evaluated. For the types, enter min, max, or neither.