To find the amount withheld as a function of the number of ice cream bars sold, we must compose the 2 given functions in the problem
The 2 funtions are:

As we want to find the amount withheld as a function of the number of ice cream bars sold, we need to compose S(x) into W(x).
Mathematically it is represented as:

Then, we need to calculate the composition

So, the amount withheld as a function of the number of ice cream bars sold is

Where x is the number of ice cream bars sold