3) A textile firm uses 15 tons (15 000 kgs) of cotton during a year. The price of cotton is 15 TL per kg. The holding cost of keeping cotton in inventory is equal to 20% of the buying price. The acquisition cost per one order is calculated as 100 TL. Given this; calculate a) optimal (economic) order size that will minimize the costs b) How many orders must be given in a year to minimize the costs and at what intervals? Note: You may use the formula to calculate EO