Natural resources

5. extracting oil or minerals from the ground
6. a minerals ability to split easily along flat surface
7. urban areas that heat up more quickly and retain heat better than non urban areas
9. coal, oil, natural gas, and other fuels that are ancient remains of plants and animals
11. a spontaneous process in which unstable nuclei lose energy by emitting radiation
13. any natural resource (as wood or solar energy) that can be replenished naturally with the passage of time
15. power derived from the wind(as by windmills)
16. a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
17. polyculture, crop rotation, labor intensive
19. a liquid mixture of complex hydrocarbon compound; used widely as a fuel source
20. involves global management of earths natural resources to ensure that current and future energy needs will be met without harming the environment

1. movement of people from rural areas to cities
2. a resource that cannot be reused or replaced easily
3. the act of drilling a hole in the earth in the hope of producing petroleum
4. the act of cutting down trees, can cause erosion
8. agriculture that has minimal/no impact on the land. it is often thought that these foods are healthier or safer in some ways
10. the color of a material in powdered form
12. Farming
14. energy from the sun
18. brownish-black materials produced by partial decompostion of plant remains