What are some of the main landforms and waterways found in North Africa?

What are seismic dampers and why are they important?

What evidence does the writer give to support his argument about coral reefs? a) he speaks of the activities of coral polyps. b) he describes the composition of the great barrier reef. c) he emphasizes the ways in which coral reefs are fragile. d) he points out the ways that scientists do research on the reefs.

What was the great rift valley formed by