A tight oligopoly refers to:​ a. ​an industry in which the top four firms supply more than 60 percent of the market, have unstable market shares, and do not cooperate with each other. b. ​an industry in which a single firm has over half the market share and no close rival. c. ​an industry in which the top four firms supply more than 60 percent of the market, have stable market shares, and cooperate with each other. d. ​a single firm that controls the entire market and can block entry. e. ​an industry in which a single firm supplies over one-third of the entire market, the market share is stable, and the firm cooperates with other firms in the industry.

c

Explanation:

An Oligopoly is when there are few large firms operating in an industry. While, a monopoly is when there is only one firm operating in an industry.

Oligopolies are characterised by:

price setting firms

product differentiation

profit maximisation

high barriers to entry or exit of firms

downward sloping demand curve

A tight oligopoly is when at most 8 firms hold at least 50% of the market share. there is usually cooperation among the firms

a recipe serves 8 people, and calls for 5 lbs of apples and 2 cups of flour. you want to prepare it for 24 people. divide 24 by 8 to get 3, and then multiply your ingredients by 3.

so for 24 people, you'll need 15 lbs of apples, and 6 cups of flour.