Question 2
There are $99$ numbers that are placed around a circle, each one is either $1$ or $-1$. The product of each block of $10$ adjacent numbers along the circle is then computed. Let $S$ denote the sum of these $99$ products. If there is at least one instance of $1$ and at least one instance of $-1$ around the circle, what is the difference between the maximum value and the minimum value of $S$?