I,

1. dump

2. up with

3. because

4. pollution

5. contaminate

II,

6. The water is polluted so all the aquatic animals are dead.

7. If we throw garbage into the lake, the lake will clean.

8. will

9. Herbicides are an example of pollution in agriculture.

10. Sarah has a headache because she works in a noisy office.

-----------------

I,

1. B

2. A

3. A

4. D

5. C

II,

1. D

2. D

3. C

4. C

5. A

6. D

7. C

8. A

9. D

10. A

III,

1.  One effect of global warming is that sea level are rising because the polar ice caps are melting.

2. The global population has increased because of much better nutrition levels.

3. Nuclear explosions and detonations of nuclear weapon lead to radioactive pollution.

4. More and more roads are being built; as a consequence, air pollution is rising.