Birdie Sdn Bhd imports and markets special floating golf balls to various clients throughout Malaysia. The company is reviewing its purchasing policy. It expects to sell 624,000 balls next year. The cost price of each ball is RM2.40 and is sold in dozens. Storage and other carrying cost are estimated at RM0.10 per ball. Ordering cost is RM20 per order. The delivery time is two weeks and safety stock level are 12,000 balls. The demand for such balls per year is about 52,000 dozen.

Calculate: The re-order levels.