Today, about _____ million Americans are affected by poverty

A researcher who tests the same individuals over thirty years, when they are 10, 20, 30, and 40 years old, is conducting:

cohort research. longitudinal research. continuous research. cross-sectional research.

Three-year-old Serena refers to a squirrel as a "rabbit," but points correctly to a squirrel when given the word squirrel in a comprehension task. Serena probably has

A) difficulty discriminating between squirrels and rabbits. B) difficulty recognizing squirrels. C) difficulty pronouncing the word squirrel. D) a hearing disability.