Warehouse stores such as Costco and Sam’s Club are the shopping choice of many Americans because of the low cost associated with bulk shopping. When a new warehouse grocery store called WinCo Foods was opened in Moreno Valley, California, an advertising mailer claimed that they were the area’s “low price leader.” They compared their prices with those of four other grocery stores for a number of items purchased on the same day. A partial list of the items and their prices is given in the following table.

a. What are the blocks and treatments in this experiment?

b. Do the data provide evidence to indicate that there are significant differences in prices from store to store? Support your answer statistically using the ANOVA printout that follows.

c. Are there significant differences from block to block? Was blocking effective?

d. The advertisement includes the following statement: “Though this list is not intended to represent a typical weekly grocery order or a random list of grocery items, WinCo continues to be the area’s low price leader.” How might this statement affect the reliability of your conclusions in part b?