After the defeat of the Confederacy, describe the Reconstruction Era.

Reconstruction, in U.S. history, the period (1865–77) that followed the American Civil War and during which attempts were made to redress the inequities of slavery and its political, social, and economic legacy and to solve the problems arising from the readmission to the Union of the 11 states that had seceded at or ...

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.