A congestion toll imposed on a highway driver to force the driver to take into account the increase in travel time she imposes on all other drivers is an example of internalizing the externality

The airline dominating Charlotte, North Carolina, once contended that it could not overcharge for fear of potential competition, if not at Charlotte, then at Raleigh, a two-hour drive away. Do you find this argument compelling, given the theory of contestable markets?

In answering the question, assume a graph in which dollars are measured on the vertical axis and output on the horizontal axis. Refer to the information. For a purely competitive firm, total revenue graphs as a:

A. straight, upsloping line. B. straight line, parallel to the vertical axis. C. straight line, parallel to the horizontal axis. D. straight, downsloping line.