According to Anthony and Govindarajan (2000), every control system as at least four elements:

1. A detector or sensor that measures what is happening 2. An assessor that determines the significance of what is happening by comparing it with a standard or expectation 3. An effector (feedback) that alters behaviour if the assessor indicates the need to do so 4. A communication network that transmits information between the other elements For the following scenarios, identify how each of the four elements might occur:

a. A quality control system at a plant that manufactures peanut butter

b. The product design control system for a computer manufacturer

c. The customer service control system at a telephone company