In the above figure, moving from producing 50 guitars and 50 ukuleles to producing 25 guitars and 75 ukuleles, the opportunity cost of one ukulele is

The bowed out (concave) shape of the production possibilities curve implies that as production of one good

A) increases, society must forgo increasing amounts of another good. B) increases, production of other goods increases as well. C) decreases, production of other goods decreases as well. D) increases, society must forgo decreasing amounts of another good. E) increases, society can obtain a free lunch.

Which of the following lists contains, in this order, natural resources, physical capital, and human capital?

a. For a shoe factory: leather, hand tools, the managers' knowledge of shoe making. b. For a steel mill: the blast furnaces, iron ore, the workers. c. For an airline: oil used to make jet fuel, the pilots' knowledge of flying, jets. d. None of the above is correct.