On average, what value is expected for the t statistic when the null hypothesis is true?

Young laboratory monkeys who saw their parents express fear to a live snake later showed fear themselves while viewing a live snake for the first time. This new fear would be the result of

a. observational learning. b. behaviorism. c. situationism. d. exposure and response prevention. e. token economies.

In medicine, a number of symptoms that occur together and characterize a specific illness or disease is known as a ___________

a. complex b. simplex c. syndrome d. synergism