While riding on a train, David notices that the trees and telephone poles close to the tracks seem to flash by, while the buildings, trees, and mountains that are farther away seem to move by more slowly. This phenomenon is called ________

The chief characteristic of bulimia nervosa is

a. self-induced vomiting. b. binge eating. c. self-starvation. d. a preoccupation with food.

A researcher mails permission letters to parents and stipulates that if the permission form is

not returned, the parent has indirectly agreed to allow their child to partake in the study. This procedure is: A) passive parental consent. B) active parental consent. C) a violation of confidentiality. D) informed consent waiver.