The manager of a supermarket in Hoboken, New Jersey, has two local newspapers competing for weekly ads. The salesperson for newspaper A claims that although A's rates are significantly higher than newspaper B's, paper A has the best circulation in the market. Also, readership studies show that area residents really scrutinize the paper's pages. The salesperson for newspaper B concedes that the publication does not have the widest circulation, but points to readership studies showing that its ads are equally effective. "Why pay twice as much for an ad, when my paper can do as strong a job for less money?" This problem has been unresolved for some time. Recently, the store had nine scanner checkouts installed. The manager would like your advice on how to use the store's scanner sales data to compare the effectiveness of the two newspapers.