The market for ice cream, like most markets in the economy is highly competitive. Each buyer knows that there are several from which to choose, and each seller is aware that his product is similar to that offered by other sellers. As a result, the price of ice-cream and the quantity of ice cream sold are not determined by any single buyer or seller. Rather price and quantity are determined by all buyer and sellers as they interact in the marketplace. Economists use the term competitive market to deceive a market in which there are so many buyers and so many sellers that each has a negligible impact on the market price. Each seller of ice cream has limited control over the price because other the sellers are offering similar products. A seller has little reason to charge less than the going price and if he charge more buyers will market their purchases elsewhere. Similarly no single buyer of ice cream can influence the price of ice cream because each...