Unit 1 Lesson B

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Across
  1. 5. anything that has mass and takes up space
  2. 6. sound waves above human hearing
  3. 8. the release of energy from unstable atoms
  4. 9. the movement of a liquid gas or electricity
  5. 10. material that provides energy when burned or used
Down
  1. 1. repair and care to keep something working
  2. 2. make products in a factory
  3. 3. knowing something well through experience
  4. 4. the first model of a new product
  5. 7. an object that orbits a planet or is used for communication