The first useable test of intelligence was developed by Alfred Binet, a scientist who was asked by the __________ government to develop a measure to identify school children who had special needs

About what percentage of the genes in any two people are identical?

a. Approximately 75% b. 25% or less c. Over 99% d. Approximately 50%, depending on race

To study the effects of aging, Professor Drake compares the reaction times of 60-year-olds with those of 30-year-olds. She tests all younger subjects in the morning, and all older subjects in the afternoon

She concludes that aging causes a decline in the speed of responses. This study lacks ________ because of potential ________. A) external validity; demand characteristics B) external validity; confounds C) internal validity; demand characteristics D) internal validity; confounds