9.2 Soon after the United States revealed the discovery of a single mad cow in December 2003, more than 40 countries slapped an embargo on U.S. beef. In addition, some U.S. consumers stopped eating beef.

In the three weeks after the discovery, the quantity sold increased by 43% during the last week of October 2003, and the U.S. price in January 2004 fell by about 15%. Use supply-and-demand diagrams to explain why these events occurred.