(Critical Thinking) At the beginning of the year, Civella, Inc. budgeted the following for an estimated production volume of 10,000 units: Budget estimates based on 10,000 units: Sales $200,000 Direct Materials $20,000 Direct Labor $30,000 Manufacturing Overhead: Variable MOH $30,000 Fixed MOH $10,000 There were no beginning balances in any of the inventory accounts. At the end of the year, the ending balance of work in process was zero. Actual manufacturing overhead incurred was $39,500 and manufacturing overhead was under-applied by $1,500. Since manufacturing overhead was applied on the basis of budgeted/expected production volume, how many units were actually produced during the year?