SUB- and SUP- words

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Across
  1. 2. also known as Clark Kent, superhero
  2. 3. someone with exceptional powers or abilities
  3. 4. of less importance/ lower in rank or position
  4. 5. to take the place of another person in authority
  5. 7. to be completely covered in a body of liquid
  6. 8. the smaller piece of information that comes after a title
Down
  1. 1. vehicle used to explore underwater
  2. 5. to be responsible for someone else and what they are doing
  3. 6. x-ray vision, the ability to fly, can read minds, super fast
  4. 7. anotherword for the tube (also a sandwich shop)