Mesa Solutions needs 300 units of aluminum panels each week for its sign-making business. The carrying/holding cost per unit per year is $20 and the fixed ordering cost is $900.

1. What is the optimal quantity to order so that inventory cost is minimized?
2. How often (approximately every how many days) should Mesa Solutions order the inventory of aluminum panels? Assume a 365-day year.
3. What is the annual carrying/holding cost at this optimal order quantity?