sheffield company is evauluating its performance at year end within its variable its variable costing system. the company uses standard costing and budgeted for $14600 of fixed MOH costs to support budgeted production of 3100 units the purchasing departmernt couldnt get ots hands on as many raw material as it had hoped so production was only 1980 units this year variable manufacturing costs and variable operating cost were on budgeted at $19 per unit and $3 per unit , respectively,