Which of the following organizations is an example of a nongovernmental organization that focuses primarily on political advocacy?

What is the best way to reduce measurement error?

A) Develop and apply a good operational definition. B) Use a ratio scale of measurement. C) Keep the number of participants equal in all groups. D) Conduct research at the experimental level.

Oil accounts for ______ of all energy consumed in the United States.

A. 19% B. 24% C. 36% D. 90%