Belk has a chain of department stores across the South. Top management requires that each store manager collect, maintain, and respond to customer complaint letters and calls. Each store keeps a file of complaint letters that have been received. Top management is considering establishing a more formalized method of monitoring and evaluating the response managers give to the complaint letters. They want some information that will tell them whether they need to develop such a formalized program or whether they can leave well enough alone and allow managers to use their discretion in handling the complaints. They want to review a sample of these complaint letters and the response to them.

a. What sampling plan should be used?

b. Why?