1. The management of Harper Corporation, a manufacturing company, has provided the following financial data for December: Sales ...... Variable production expense. Fixed production expense Variable selling expense Fixed selling expense... Variable administrative expense. Fixed administrative expense.... $480,000 $76.000 $85.000 $18.000 $83.000 $46.000 $108.000 The contribution margin for December was: A. $204,000 B. $64,000 C. $340,000 D. $319,000