The manager of a warehouse for a telephone company is involved in a process that receives expensive circuit boards and returns them to central stock so that they can be reused at a later date. Speedy processing of these circuit boards is critical in providing good service to customers and reducing capital expenditures. The data in Warehse represent the number of circuit boards processed per day by a subgroup of five employees over a 30-day period.
a. Construct control charts for the range and the mean.
b. Is the process in control?