The following memorandum is from the business manager of Happy Pancake House restaurants. "Recently, butter has been replaced by margarine in Happy Pancake House restaurants throughout the southwestern United States. This change, however, has had little impact on our customers. In fact, only about 2 percent of customers have complained, indicating that an average of 98 people out of 100 are happy with the change. Furthermore, many servers have reported that a number of customers who ask for butter do not complain when they are given margarine instead. Clearly, either these customers do not distinguish butter from margarine or they use the term 'butter' to refer to either butter or margarine."