A(n) ________ variable is calculated from within the model. A(n) ________ variable can never be taken as given

A country currently is using all its land to produce wheat and grapes. However, the land most suited to growing grapes is being used to produce wheat, and the land most suited to growing wheat is being used to produce grapes. Which of the following statements is true?

a. Production of both wheat and grapes can be increased by shifting tracts of land to their best uses. b. Production of both wheat and grapes can be increased only if more land becomes available. c. production of wheat can increase only if production of grapes decreases. d. Production of grapes can increase only if more labor and machinery become available. e. Production of neither wheat nor grapes is possible without more land becoming available.

Figure 2-2

Assume that U.S. agricultural land is used either to raise cattle for beef or to grow wheat. represents the production possibility frontier for beef and wheat. The opportunity cost of moving from point G to point F equals
a.
0.25 million bushels of wheat
b.
1.75 million bushels of wheat
c.
0.125 bushels of wheat
d.
8 bushels of wheat
e.
2 bushels of wheat