Problem 4: A company wishes to bottle 2 different drinks. It takes 2 hours to can one gross of drink A, and it takes 1 hour to label the cans. It takes 3 hours to bottle one gross of drink B, and it takes 4 hours to label the cans. The company makes a $10 profit on one gross of drink A and a $20 profit on one gross of drink B. Given that the bottling department has 20 hours available, and the labeling department has 15 hours available, find out how many gross of drink A and drink B must be packed in order to maximize the profit. (Use Graphical Method)