The first effective tests of mental faculties were developed by ____

In the previous question, how comfortable the chairs were is a(n):

a. confound b. moderator c. third variable d. mediator

Thomas is in a detention center where he can earn points for good behavior and for academic achievements and then trade in the points for money. This illustrates a:

A) training school. B) group home. C) token economy. D) all of the above