3. (20 marks) The office manager for the Gotham Life Insurance Company orders letterhead stationery from an office products firm in boxes of 500 sheets. The company uses 6,500 boxes per year. Annual carrying costs are $3 per box, and ordering costs are $28. The following discount price schedule is provided by the office supply company: Order Quantity ( in boxes) Price per Box 200-999 $16 1000-2399 514 3000-5399 6,000+