Jerry's Phone Service is a monopoly. Jerry finds the price of his service by looking at the price demanded at the chosen quantity.
A monopoly refers to situation where one producer (or a group of producers acting in concert) controls supply of a goods and services, and where the entry of new producers is prevented or highly restricted. In order to make profit, Monopolist firms keep the price high and restrict the output, and show little or no responsiveness to the needs of their customers.