Hector is buying granola to make trail mix. There are three different types of granola to choose from. The Crunchy Granola is a 8.5 oz bag and it costs $2.25 per ounce. The Sweet Granola is a 15 oz bag and costs $1.10 per ounce. The Maple Granola costs $1.35 per ounce and is sold in a 12.75 ounce bag. Hector would like to buy the least expensive bag for his trail mix. If all he has is a $20 bill, what change should he expect after buying the cheapest bag of granola?