A natural monopoly exists whenever a single firm:

is owned and operated by the federal or local government.

is investor$-$owned but has been ginted the exclusive right by the government to operate in a market.

earns economic profits in the long run.

has gained control over a strategic input of an important production process.

experiences economies of scale over the entire range of production that is relevant to its market.

Which of the following is not a characteristic of monopolistic competition?

product differentiation

lack of barriers to entry and exit in the long run

many competing producers

tacit collusion

advertising

Which of the following is not a characteristic of monopolistic competition?

product differentiation

lack of barriers to entry and exit in the long run

many competing producers

tacit collusion

advertising