A(n) is defined as the interrelationship between living beings and environment.1. ecosystem 2. life support system3. climate system4. atmospheric system

Which of the following factors is not used to measure a country’s standard of living? a.) life expectancy b.)educational levels c.)divorce rates d.) gross income

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.

Explain why the rate of urbanisation is in the way it is between developed and undeveloped countries.