Humans are always on the move, but in general they tend to settle: a. close to mineral deposits like coal. b. along the coastlines and rivers. c. in the mountains when possible. d. near necessary resources.

Which of the following is not a challenge to instituting sound global environmental policies? a. most changes are inexpensive and easy to implement. b. elected leaders who support unpopular environmental issues often are not re-elected. c. economic considerations outweigh environmental ones in many societies. d. there is no way to enforce international environmental agreements.

What is the approximate chemical composition of the solar nebula?

70 pts answer the following questions in full sentences and paragraphs, using at least 150 words, in the essay box below. 1. which organisms are carnivores? herbivores? omnivores? 2. if the ecosystem is balanced, which populations should be the largest? the smallest? 3. imagine a group of hunters kills half of the rabbit population. how will the other organisms be affected? 4. imagine disease kills 85 percent of the wolf population. how will the other organisms be affected? 5. imagine a foreign mountain lion species is introduced into the ecosystem. how will the other organisms be affected?