Across
- 3. to do all the time ; routine
- 4. to use again
- 6. materials found in nature
- 7. a number that represents a thousand times one thousand times (1,000,000)
- 9. make dirty or harmful to health
- 10. an artificial substance made from chemicals
Down
- 1. meant to be thrown out after use
- 2. a layer of gasses surrounding the earth or a planet
- 5. A gas that absorbs and gives of heat
- 8. power electricity or heat created by sunlight