What is a proportional stratified sample?

General intelligence has ___ heritability relative to more specific abilities, such as verbal and spatial abilities

a. lower b. higher c. virtually zero d. None of the above

James, a 15 year old, thinks he won the parenting lottery – his parents set no rules for him and let him come and go as he pleases. Later on in life, he may be prone to developing which disorder?

a) Anxiety b) Depression c) Substance dependence d) All of the above