Which author of Strangers to Ourselves argued that introspection does not provide a direct pipeline to selfknowledge?

Data from the Seattle Longitudinal Study demonstrated that as adults grow older, their intellectual functioning increases if they

do paid work that is intellectually challenging. do any type of work as long as they are paid for it. do work that represents an increase in their previous pay level. perform the tasks of everyday life.

Why is the United States considered a developed country?

What will be an ideal response?