The correct answer is x= 94
Remember your formula is 180(n-2) where n=number of sides. So start out by dividing by 180, then add 2 to get the sides.
There are 10 millimeters in 1 centimeter. one millimeter is one-tenth of a centimeter.
For this case we have the following variables:
x: number of months
f (x): number of caps sold
The function that models the problem is given by:

By the time the store sells 64 caps we have:

From here, we clear the number of months:

Answer:
the store sells 64 caps in 3 monts
A. month 3