American airlines vs southwest. Which airline will prevail in the US airline market, american or southwest or will both survive?

Concepts to use(please use at least 2 or more of these concepts for the paper,weve been only taught these concepts):
1.law of diminishing marginal returns
2.economies of scale
3.normal profits and economic profits
4.price elasticity of demand
5.CPI and income & substitution effects.
6.Short run and long run shut down points
7.Opportunity costs
8.Competitive market model assumptions
9.Supply and demand dynamics
10.Price discrimination

Relating to at least 2 or more of these concepts, the paper needs to show the concepts through graphs, the graphical requirements are:
1.Must have a market(supply and demand) graph, and
2.Must have either a supply(driven by cost) graph that contains MC, AC etc, or a demand(how changes in relative prices affects consumer choice)graph.

Should use at least four different acceptable research sources excluding the course textbook. The quality and quantity of these references will determine the amount of points earned for research.

Acceptable Sources: In general, citations from Internet websites will NOT count as an acceptable source unless the citation is from a U.S. government website. The Internet can be used to find on-line versions of publications, but such citations should be made only for articles that are published in paper form (i.e., can be found in a library). For instance, you could use a New York Times article that is downloaded from the Internet. Encyclopedias and abstracts are not valid sources. Cutting and pasting information from the Internet is plagiarism.

Recommended Sources:

The Wall Street Journal
New York Times online
CNN Financial News online
The Economist (magazine)
The National Review
any academic journal
nonacademic journals
library books
government publications (e.g., those of the Commerce Department or U.S. Census)