TNG Co expects annual demand for product X to be 255,380 units. Product X has a selling price of $19 per unit and is purchased for $11 per unit from a supplier, MKR Co. TNG places an order for 50,000 units of product X at regular intervals throughout the year. Because the demand for product X is to some degree uncertain, TNG maintains a safety (buffer) inventory of product X which is sufficient to meet demand for 28 working days. The cost of placing an order is $25 and the storage cost for Product X is 10 cents per unit per year. TNG normally pays trade suppliers after 60 days but MKR has offered a discount of 1% for cash settlement within 20 days. TNG Co has a short-term cost of debt of 8% and uses a working year consisting of 365 days.

Required: (a) Calculate the annual cost of the current ordering policy. Ignore financing costs in this part of the question. (b) Calculate the annual saving if the economic order quantity model is used to determine an optimal ordering policy. Ignore financing costs in this part of the question. (c) Determine whether the discount offered by the supplier is financially acceptable to TNG Co. (d) Critically discuss the limitations of the Economic Order Quantity model as a way of managing inventory.