Why can the geologic record be analyzed by looking at different rock layers? a : all layers have the same age. b : the layers have different ages with the youngest layers on top. c : the layers have different ages with the oldest layers on top. d : the layers have different ages with the youngest layers on bottom.

How is the male reproductive system different from other body systems? it isn’t necessary to vital signs. it monitors other body systems, and adjusts if necessary. it transports items from one system to another. it is the only system that produces hormones in the male.

Which of these is not a nucleotide base found in dna?

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.