The embryonic disk has ___ layer(s)

Which of the following statements relate to girls' decline in self-esteem in adolescence?

a. Normal physical development is at odds with a cultural ideal of thinness. b. Boys typically have a more negative body image than do girls. c. Girls' scholastic achievement is typically lower than that of boys. d. All of these.

The coefficient of correlation conveys:

a. the size and direction of the relationship between two variables. b. whether one variable causes the other variable to happen. c. the unintended changes in a subject's behavior due to the experimenter's cues. d. whether or not the principle of falsifiability applies to each variable.