A manufacturer incurs the following costs in producing $x$ waffle irons in one day for $0 < x < 100$: fixed costs, 310 dollars; unit production cost, 21 dollars per waffle iron; equipment maintenance and repairs, $0.06 x^2$ dollars.

(A) Find the average cost function $\bar{C}(x)$.

(B) List all the critical values of $\bar{C}(x)$. Note: If there are no critical values, enter 'NONE'.

(C) Use interval notation to indicate where $\bar{C}(x)$ is increasing.
Note: Use 'INF' for $\infty$, '-INF' for $-\infty$, and use 'U' for the union symbol.
Increasing:

(D) Use interval notation to indicate where $\bar{C}(x)$ is decreasing.
Decreasing:

(E) List the $x$ values of all local maxima of $\bar{C}(x)$. If there are no local maxima, enter 'NONE'.
$x$ values of local maximums =

(F) List the $x$ values of all local minima of $\bar{C}(x)$. If there are no local minima, enter 'NONE'.
$x$ values of local minimums =

You can earn partial credit on this problem.