Two siblings, David and Alexis Rose, enjoy baking bread and making apple pie. Alexis takes 2 hours to bake a loaf of bread and 1 hour to make a pie. David takes 4 hours to bake a loaf of bread and 4 hours to make a pie.

a. What are David's and Alexis's opportunity costs of baking bread?

b. Who has the absolute advantage in making bread?

c. Who has a comparative advantage in making bread?

d. If David and Alexis both decide to specialize to increase their joint production, what should David produce? What should Alexis produce?

e. The price of a loaf of bread can be expressed in terms of an apple pie. If David and Alexis are specializing in production and decide to trade with each other, what range of ratios of bread and apple pie would allow both parties to benefit from trade?