For each of the following scenarios, determine which market model best describes the scenario. Then identify the number of firms, the type of product, and the ease with which new firms can enter the market under this market structure.
Scenario Number of Firms Type of Product Entry Market Model a. Hundreds of colleges serve millions of students each year. The colleges vary by location, size, cost, and educational quality, which enables students to match schools to their diverse preferences.
b. Hundreds of high school students who require tutoring in algebra choose among dozens of tutoring companies offering similar services.
c. Three airlines operate between San Francisco and San Diego. There are not enough potential customers to share the route with a fourth airline without causing the average costs of the existing competitors to rise substantially.
d. Consumers view all airlines as the same service and will select the least expensive one. The government has granted the U. S. Postal Service the exclusive right to deliver mail.