Final answer:
A single gas station on a lonely highway exit represents a geographic monopoly, where market barriers like transportation costs prevent competition.
Step-by-step explanation:
A single gas station on a lonely highway exit is an example of a geographic monopoly. This occurs when there is only one provider of a service or good in a specific geographic location, where market barriers such as distance and transport costs prevent competitors from entering easily. Unlike a natural monopoly, which is efficient due to economies of scale and typically regulated by the government, or a technological monopoly that arises from control over a unique technology, a geographic monopoly exists simply because it is not economically feasible for multiple competitors to serve an area with a small customer base.