Artisan Works is owned and operated by a craftsman who makes replicas of historic firearms for museums sportsmen and collectors The data are as follows Sales price per unit $800 Variable cost per unit 470 Foxed costs per month 7.920 If Artisan expects to sell 40 units per month what is his margin of safety expressed in units per month? O A. 40 units OB. 16 units O C. 14 units OD. 64 units