During the month of January, Maison Company incurred a total product cost of $112,000. The company spent twice as much on direct materials as on direct labor and the company's conversion cost is twice its prime cost. During January, the direct materials cost was

Statistical process control charts: a. indicate to the operator the true quality of material leaving the process. b. display upper and lower limits for process variables or attributes and signal when a process is no longer in control. c. indicate to the process operator the average outgoing quality of each lot. d. display the measurements on every item being produced. e. are a graphic way of classifying problems by their level of importance, often referred to as the 80-20 rule.