Technology crossword

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Across
  1. 3. manually operated firearm known for its accuracy and reliability
  2. 6. military tactic where opposing forces dig into the ground
  3. 8. used for trenches
  4. 9. underwater weapons
Down
  1. 1. air combat
  2. 2. a type of gun providing high rate of fire
  3. 4. could fly at high altitudes and cover long distances, making them useful for strategic bombings
  4. 5. known for severe blistering effects
  5. 7. caused severe respiratory problems and damage to eyes and skin