PIAB Enterprises has identified the following as having an impact on the company's quality costs:

1. Inspection of manufactured goods on assembly line

2. Warranty repairs

3. Employee training

4. Quality engineering/design

5. Units repaired at customers' site

6. Product testing

7. Customer complaints

8. Product liability

9. Rework of defective goods before transfer to finished goods

10. Preventive maintenance for equipment

Required:

Classify the eleven costs as prevention, appraisal, internal failure, or external failure.