Mary has a weekly allowance of $24 to spend on soda and coffee.  Let 40 cups be the maximum amount of soda she can buy for the money.  Let $.40 be the price of 1 cup of coffee.  Assume that regardless of prices Mary always prefers to consume coffee and soda in one-for-one combinations, i.e. a cup of soda with each cup of coffee. Draw Mary's budget line and her indifference curves.  Determine her best choice.