What is the most critical aspect of the experimental method that allows us to make statements about cause and effect based on experimental data?

More than half the world's nations are at least somewhat __________

a. authoritarian b. democratic c. oligarchic d. theocratic

Which U.S. amendment prevents states from requiring payment of a poll tax as a condition for voting?

A) Fifteenth Amendment B) Thirteenth Amendment C) Twenty-Fourth Amendment D) Fourteenth Amendment