Which of the following is part of the geometric model? A. all object in the universe are perfect squares
B. All objects in the universe move around the sun
C. All objects in the universe revolve around earth
D. All objects in the universe move in random patterns

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.