Answer:
has increasing returns to scale over the entire relevant range of output.
Step-by-step explanation:
A monopoly is when there is one firm operating in an industry. A monopoly firm is a price setter and usually has high barriers to entry of firms into the industry. A monopoly earn economic profit in the long run.
A natural monopoly is when a firm is a monopoly because it has increasing returns to scale over the entire relevant range of output or because of high start up costs.
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