How does deforestation affect the patterns of river flow

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.

In the late 1990s, brazil’s poor people protested about crowded cities land distribution mining permits industrial pollution

Hey, i was what is consisted in a sustainable city? like what unique designs they have, etc. for answering ; )