Heather's Crossword Puzzle

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Across
  1. 4. Heather's best friend.
  2. 5. Sally and Heather are _______.
  3. 6. Sally's best friend.
  4. 7. The teacher has announced a Science _______.
Down
  1. 1. Sally and Heather have a _________.
  2. 2. A mountain filled with lava.
  3. 3. Something that explodes from the science Project.
  4. 4. A ______ project.