Figure 2-10 -Refer to Figure 2-10,Panel (A)and Panel (B).A Shift of the Shift

Multiple Choice

Figure 2-10

-Refer to Figure 2-10,Panel (a) and Panel (b) .A shift of the economy's production possibilities frontier from Panel (a) to Panel (b) could be caused by

A) unemployment.
B) an improvement in sofa production technology.
C) an improvement in tractor production technology.
D) an improvement in both sofa and tractor production technology.