A scientist wants to determine the age of a rock. The rock contains an index fossil and an ancient relative of a living organism. Which is more useful for dating the rock, and why?

Most of the volcanic activity that occurs in the ring of fire is a result of the a. formation of mantle plumes away from plate boundaries. b. subduction of one plate under another. c. movement of two plates away from each other. d. sliding of one plate past another.