A researcher studying income in poor neighborhoods learns the mean income is $25,000 per year. A family earning $31,000 per year has a $6,000 ______________________.

In the context of extraneous variables, "history" refers to

a. events that can influence the dependent variable, that occur between the first and second measurement of that variable. b. events that can influence how accurately one can control the independent variable. c. differences in participants' knowledge of the subject matter of the experiment in which they are participating. d. biases brought to the study by one pre-selected group and not another.

What is likely to be the primary motivation for the president in utilizing an executive agreement?

a. to include the Senate in diplomatic activity with foreign leaders b. to establish an agreement with a foreign government that does not require Senate ratification c. to demonstrate a bipartisan spirit in the conduct in passing legislation with Congress d. to appease party supporters