Brands of ready-to-eat cereal by Kellogg, Post, General Mills and Quaker [for example Frosted Flakes, Raisin Bran and Cheerios] account for more 85 percent of all breakfast cereals sold. Here the ready-to-eat cereal industry is an illustration of: (w) pure competition among several brands of cereal. (x) pure monopoly. (y) monopolistic competition among several cereal firms producing several brands. (z) oligopoly since almost all main brands are produced by a few large firms.
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