Across
- 3. an igneous rock
- 5. Subdivided into two regions, upper and lower
- 7. liquid layer of the earth
- 9. iron
- 10. vibrations in the earth that transmit energy
- 11. nickel
Down
- 1. solid sphere of mostly iron and nickel
- 2. a substance's mass per unit of volume
- 4. an aphanitic (fine-grained) extrusive igneous rock
- 6. heat transfer that can only happen in liquids and gases
- 8. the earth's outermost and thinnest layer