Answer:
a. oligopoly.
b. an economic profit.
c. economic profits will fall.
Explanation:
An oligopoly can be defined as a market structure comprising of a small number of firms (sellers) offering identical or similar products, wherein none can limit the significant influence of others.
Hence, it is a market structure that is distinguished by several characteristics, one of which is either similar or identical products and dominance by few firms.
The characteristics of an oligopolistic market structure are;
I. Mutual interdependence between the firms.
II. Market control by many small firms.
III. Difficult entry to new firms.
Hence, a firm operating in the United States of America with only two other competitors in the industry is likely to be an industry that would be characterized as oligopoly.
Additionally, business firms operating in this industry (oligopolistic market) will likely earn an economic profit. Also, if foreign business firms begin supplying the product, increasing the number of competitors, it is likely that economic profits will fall because the industry is now being competitive and controlled by other business firms.