If you conducted a survey of 1,000 women over the age of 85 and asked them if they were widows, you should expect that about how many of them would answer "yes."

Two very important factors that influence the strength of classical conditioning are ____

a. ?validity and reliability b. ?contiguity and contingency c. ?congeniality and conviviality d. ?spontaneity and flexibility

In a study on the effects of sleep on driving performance, sleep would be the:

a. control group. b. independent variable. c. experimental group. d. dependent variable.