In a study that examined gender roles in 12 traditional cultures, same-gender play groups occurred in about 30 to 40% of 2- to 3-year-olds, but occurred in what percentage in middle childhood?

Social categorization is advantageous because it

a. leads to more accurate social perception. b. encourages us to take longer to make judgments about others. c. frees up cognitive resources. d. is generally based on realistic assumptions.

Developmental tasks can be viewed as

a. the physical challenges in a stage of development. b. the unfolding of the epigenetic principle. c. competencies that lead to mastery of the environment. d. unrelated to stages of a person's development.