Johnson's Artisan Bakery is experimenting with two new croissant recipes. One recipe calls for 302.5 grams of bread flour and 30 grams of butter, while the other calls for 375 grams of bread flour and 43 grams of butter. The first recipe would yield $2.5 per croissant, and the second would yield $3.2 per croissant. Although the chefs like both recipes, they agree that since the second recipe requires more butter, they should probably only make half as much as the first. On a typical day, Johnson's would stock 20 kilograms of bread flour and 2 kilograms of butter. Formulate a linear programming model that maximizes the profit.