Tristan's Puzzle #1

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Across
  1. 2. number of inches in a foot
  2. 4. the number of right angles on a square
  3. 6. number of wheels on 4 cars
  4. 8. the answer to 8 tens and 18 ones
  5. 9. the number of eggs in two dozen
Down
  1. 1. 11 groups of ten
  2. 3. another name for corners on a 2D shape
  3. 5. number of inches in 3 feet
  4. 7. the number of sides on three triangles
  5. 9. half of 500