In the 1992 election, the membership of Congress was altered significantly by an increase in the number of

"External validity" of an experiment refers to the extent to which

a. the operational definitions of variables really do represent the concepts they are meant to capture. b. we can be confident that the experiment is testing the hypothesis we think it is testing. c. we can make causative statements about the relationship between the dependent and independent variables. d. the results of an experiment can be generalized across people, settings, times, treatments, and outcomes.

In the 19th Century, the main goal for Mexican revolutionaries was to

a. promote liberalism and equality amongst all classes of people. b. create opportunities for themselves and reduce power of foreign capitalists. c. develop a constitution more liberal than the one Spain introduced. d. firmly establish a border between the U.S. and Mexico.