Snow Cat manufactures snow mobiles and uses activity-based costing to allocate overhead cost. To produce snowmobiles, the company uses four activities. It sets up machines to produce batches of components. Assembly line employees assemble products. Completed snowmobiles are inspected for quality. Maintenance workers clean the factory after production finishes at the end of the day.

1. If $30,000 of Setup is used as an activity cost pool, which of the following would not be used as a cost driver?

1. Square feet
2. Number of setups
3. Design modifications
4. Number of employees hired