A bakery buys sugar in 15-pound bags. The bakery uses 5000 bags of sugar each year. Carrying costs are $20 per bag per year. Ordering costs are estimated at $5 per order. Assume that the bakery is open 250 days a year and its daily demand is estimated at 20 bags. It takes 5 days for each order of sugar to be filled. What is the optimal number of orders per year?
1. 200
2. 100
3. 500
4. 300
5. 400