a) The widget industry is comprised of six firms of varying sizes. Firm 1 has 35 percent of the market. Firm 2 has 25 percent, and the remaining firms have 10 percent each. What is the Herfindahl-Hirschman index for the widget industry? Based on the U.S. Department of Justice merger guidelines described in the text, do you think the Justice Department would be likely to block a merger between firms 5 and 6?
b) Grocery stores make most of their profits on soft drinks, beer, chips, and candy. A casual look at prices of these items reveals that these prices change extremely often and can vary as much as 50 percent. Is this because the wholesale price of these items fluctuates this dramatically, or is there some other possible explanation?
c) The U.S. Postal Service has been raising postal rates on a regular basis. The service had been losing money. One of the reasons is increased competition from companies such as United Parcel Service and Federal Express. Another reason is the use of faxes and e-mail, as well as electronic bill payment. With this decrease in demand for postal services, why do you think that the Postal Service is seeking a rate increase?