Engineering crossword

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Across
  1. 4. engineers that optimizing factories
  2. 5. a combo of biology medicine
  3. 6. maintains building and other structures
  4. 9. they develop aircraft and spacecraft
Down
  1. 1. physics and math are included
  2. 2. work with very hazardous material
  3. 3. finding very cheap alternatives
  4. 7. design and develop electrical machinery
  5. 8. engineers that help the climate