Jensen is running a snack shop at school but first needs to buy the items to sell. He has $72 to spend. Cosco charges $6 for a box of chocolates and $8 for a box of potato chips. The box of potato chips has 20 bags and the box of chocolates has 10 bars. The snack shop can hold 140 items the most. If he earns $14 for each box of chocolates and $12 for each box of chips, now much of each box should he buy to maximize his profits?