Step-by-step explanation:
Inflection points are where a function changes concavity (the second derivative changes signs). At x = 4, f"(x) goes from negative to positive, so that's an inflection point. However, at x = 8, we don't know if f"(x) changes signs or not. So we can't say that that's an inflection point.
We know that
[length of a circle]=2*pi*r
r=12 in
[length of a circle]=2*pi*12--------------> 24pi in
if 360° (full circle)--------------------> has a length of 24pi in
X-------------------------------------------> 8pi
X=8pi*360/24pi-----------> 120°
the answer is 120°
