Laos and Cambodia were drawn into the fighting in Vietnam___. 1. by Communists in those countries
2. when South Vietnam fell to the Communists
3. by the Khmer Rouge
4. when the United States withdrew from Vietnam

What is a reasonable action that provides safe water for communities?

Which anatomical feature would you expect to find in the fossil remains of a nocturnal species?

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.