Traci consumes two goods, lemonade and pretzels. Lemonade costs $1 per glass, and she consumes it to the point where the marginal utility she receives from her last glass of lemonade is 3. Pretzels cost $2 per bag. The relationship between the marginal utility Traci gets from eating a bag of pretzels and the number of bags she eats per month is as follows: Bags of pretzels 1 2 3 4 5 6 Marginal utility 30 20 12 6 2 0 If Traci is maximizing his utility, how much does she spend on pretzels each month