Decor Ltd has the following figures regarding its inventory: Cost price per unit NS50 per unit Storage cost per unit per year N$5 per unit Weekly demand (usage) 2 000 units Normal delivery time 2.5 weeks Insurance cost per unit per year NS5 per unit Interest rate 9% Ordering cost for 2 orders NS80 Safety stock 5 000 units There are 50 normal working weeks per year, and four weeks in one month. REQUIRED: 3.1.1 Calculate the economic order quantity (EOQ) 3.1.2 Calculate the number of orders per year 3.1.3 Determine the ordering cost per year 3.1.4 Determine the total inventory cost for the year