1. The term pollution refers to .
A. harmful substances
B. the carving away of the land
C. sand and mud left by flooding
D. the deepening of river channels

2. Scientists say that watersheds are dynamic, and that means that they .
A. don't stay the same
B. flow to a single point
C. eventually reach the ocean
D. can become polluted easily

3. Which of these would generally NOT be considered part of a watershed?
A. lake
B. river
C. wetland
D. swimming pool

4. Which of the following is a likely consequence of a flood?
A. less erosion
B. an increase in rainfall
C. the overuse of pesticides
D. a river following a new course

5. Pesticides sprayed onto plants can .
A. pollute water upstream
B. pollute water downstream
C. increase the rate of erosion
D. decrease the rate of erosion