Answer:
s is the price of each laptop that gives maximum profit
p is the maximum total profit that can be made.
Explanation:
See the attached worksheet for additional explanation. The question asks for the meaning of s (selling price) and p (total profits) at the vertex of the curve. s is in units of price/laptop, while p is in units of total profits. Implicit in this graph is a demand curve (not shown) that illustrates how demand for laptops changes as the price changes. Also not shown, but assumed, is that if the laptops are sold at a low price, the declining profit margins resuce the overall total profits. This graph incorporates the cost and demand imformation in a manner that provides a condensed view of the more important variable: total profits.