1. What happened to the rainwater?

2. Where did the rainwater go?

3. What happened to the groundwater after a lake was added to the model?
4. What caused this change in the groundwater?

5. What happened the lake after the pollutants were added to it?

6. What happened to the groundwater when pollutants were added to the lake?

7. What happened to the lake when it rained?



8. Why do you think this happened?



9. What happened to the groundwater when it rained?



10. Why do you think this happened?