Use the following to answer question: 
-(Table: Prices and Demand) Look at the table Prices and Demand. Professor Dumbledore has a monopoly on magic hats. The marginal cost of producing a hat is $18. Suppose Dumbledore can perfectly price-discriminate. How many hats will he produce?
Definitions:
Self-Stimulation Theory
A theory suggesting that behaviors are motivated by the intrinsic pleasure they provide.
Sexual Selection
A mode of natural selection where certain traits become more pronounced in a population because they are attractive to the opposite sex or aid in competitive success among the same sex.
Fecundity
the potential reproductive capacity of an individual or population, often measured by the number of offspring born.
Viability
The capacity of being alive or living successfully, often used in the context of whether a fetus can survive outside the womb or the sustainability of a project or plan.
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