1. criminal.   Hint First letter clue   2. person guilty of setting fire to property.   First letter clue   3. person who causes trouble and starts quarrels.   First letter clue   4. investigator or harsh questioner.   First letter clue   5. one who studies relation between organisms and environment.   First letter clue   6. person on horseback.   First letter clue   7. dummy or portrait of person.   First letter clue