By age 5, the brain has reached ____ percent of its adult weight

Schaie found that ______ research shows a gradual decline in intellectual ability, while ______ research, which may not be applicable to other cohorts, shows an increase in intellectual abilities throughout most of adulthood

Fill in the blank with correct word

A naturalistic observational approach is especially useful in the earlier stages of scientific investigation for all of the following reasons EXCEPT that it

a. helps researchers discover the extent of a phenomenon. b. helps researchers formulate hypotheses for further research. c. suggests what the important variables and relationships might be. d. determines cause-effect relationships between naturalistic variables.