As part of an experiment on the effects of behavior modeling, a set of raters are evaluating prosocial behavior in a series of videotapes of a preschool class. Initially, the raters were quite strict in their ratings, but after 3 hours of rating, their criteria had changed. Which type of threat to internal validity has occurred?

A. testing
B. attrition
C. maturation
D. history

Carefully study the chart above. which of the following statements best describes literacy rates in north africa? a. literacy rates are decreasing in the region. b. literacy rates are increasing in the region, and the gap between men and women is decreasing. c. literacy rates are increasing in the region, but the gap between men and women is staying the same. d. literacy rates are staying about the same in the region.

List two benefits of reforestation to the environment

No renewable resources are natural resources that are limited in supply and cannot be replaced as quickly as they are used.(true or false asnwering) a.true b.false