Rima and Song were discussing developmental theories. According to Rima, both Piaget and Vygotsky believed that biological and social factors interacted in development

Which of the following is a situation that increases the likelihood someone will act altruistically?

a. No one is actually in danger or in need of help. b. He or she has not previously helped out. c. He or she is not the only person willing to act. d. There are no situational factors that increase altruistic behavior.

Of those Americans exposed to a severely traumatic event at some time in their lives, about ______ percent will develop symptoms of posttraumatic stress disorder

a. 10 c. 50 b. 30 d. 70