Susan can pick 4 pounds of coffee in an hour or gather 2 pounds of nuts. Tom can pick 2 pounds of coffee in an hour or gather 4 pounds of nuts. Each works 6 hours per day. Assume that tom and susan specialize according to their comparative advantage to produce coffee and nuts.
a. Suppose that susan and tom could buy or sell coffee and nuts in the world market at a price of $2 per pound for coffee and $2 per pound for nuts. If each person specialized completely in the good for which he or she had a comparative advantage, how much could they earn by selling all they produce (tom's earnings plus susan's earnings)