One of Michelle's favorite things in the whole world is her grandma's banana bread. Michelle has become so obsessed with this bread that she's using her grandma's recipe and making it for her friends. She and her friends have tweaked the recipe so that they can make delicious banana chocolate chip muffins and banana squares, too. They've turned this into a side business, selling their items to local convenience stores. There's one problem: the baked goods are best when well-ripened bananas are used. They're often available at a reduced price. But when they're not, Michelle has to buy green bananas at full price and wait for them ripen. Here are the typical costs and selling prices for each product. Selling price Variable costs Bread (per loaf) $3.70 2.00 Muffin (per dozen) $5.30 2.30 Squares (per dozen) $3.70 1.40