Question 1 The study of ecology focuses specifically on: A. the world that is all around us. B. the world of living things in our planet. C. the mutual relationship between organisms and the natural world. D. anything having to do with life. Question 2 According to the text by 2050 it is believed that __________ of the earths species will become extinct if rain forest destruction continues. A. 6% B. 14% C. 25% D. 50% Question 3 Wetlands are important for all of the following reasons EXCEPT: A. they provide local habitats for many species of animals and plants. B. one-third of endangered or threatened species in the U.S. live in or are dependent on them. C. they harbor the majority of the worlds flowering species. D. they provide purification of local water supplies. Question 4 The percentage of Chinas rivers that were severely polluted in 2000 was __________; in 2002 it was __________. A. 12%; 20% B. 22%; 51% C. 32%; 65% D. 42%; 71%