If the optimum level of inventory equals to 500 units and annual requirement of inventory is 25,000 units, cost of holding the inventory is OMR 2.5 per unit. Calculate the order cost per unit? O a. OMR 12.5 per unit O b. OMR 25 per unit Oc. O c. OMR 1.25 per unit O d. OMR 0.5 per unit