Who discovered planet earth and what was the date

The european union was formally established in

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.

According to the theory of continental drift, what was the priginal state of the worlds continents