An instructor hypothesizes that doing jumping jacks will improve his students' quiz performance. On Monday, he has his class sit in their chairs for 5 minutes before completing a multiple-choice quiz on their reading assignment. On Wednesday, he has his class do 2 minutes of jumping jacks before completing the same quiz that they took on Monday. The students performed better on the quiz on Wednesday. Which is a possible threat to internal validity in this study?

In the compound republic of america, the power surrendered by the people is first divided between two distinct governments, and then the portion allotted to each subdivided among distinct and separate departments. hence a double security arises to the rights of the people. the different governments will control each other, at the same time that each will be controlled by itself.—madison, number 51 based on the quote, which of the following statements would madison have likely supported? development of political parties is necessary to ensure the security and stability of a democratic government. a government must have enough power to govern however, its power must also be limited by creating multiple branches within it. one government can not carry out the will of the people alone, therefore the establishment of two separate governments is necessary. a government must sometimes limit civil liberties of individuals to ensure the safety and security of all citizens.