Hello, Nikki,
S represents the annual sales, in million of some unit. We're not told the currency, so it could be dollars, yuan, pounds. krona, pesos, euros, whatever. When s = 55.6, add the descriptor to the number:
55.6 million
You can use your imagination as to what currency unit is referenced. But it is not needed to answer the question. [I like Iceland, so I'll mentally use krona.]
Bob