Four factors are typical of the long-lived people: moderate diet, lifelong work, ______ involvement, and a daily routine combining exercise and relaxation

A researcher was interested in whether watching violence affected children's behaviors. To examine this, he showed a violent film to one group of preschoolers and a nonviolent film to a second group of preschoolers,

and then he observed their aggression levels. In this study, the independent variable was the: viewing of the violent film. level of aggression displayed before the film. level of aggression displayed following the film. children's home environment.

How long is the fetal period?

the last three months before the child's birth from the midway point of prenatal development until birth from the second until the eighth week after conception from nine weeks after conception until birth