1. What must be true to have offspring with black fur? 2. What must be true to have offspring with white fur?
3. What must be true to have offspring with black eyes?
4. What must be true to have offspring with red eyes?
5. What must be true to have offspring with red eyes and white fur?

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.