A variation that falls between the cross-sectional and longitudinal design is the

A president's ability to implement his or her program normally decreases over time

Indicate whether this statement is true or false.

The early 19th-century view in American foreign policy circles that the United States should establish hegemony over its own hemisphere resulted in the declaration of what in 1823?

A. the Monroe Doctrine B. war against Spain C. the Treaty of Ghent D. manifest destiny E. the Roosevelt Corollary