Crossword 1

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Across
  1. 1. Circle ratio
  2. 5. Mathematics of shapes
  3. 7. Boundary
  4. 8. Bycicle spoke
Down
  1. 1. Outside measurement
  2. 2. Equal length times width
  3. 3. The width of a circle
  4. 4. Unstraight line
  5. 6. Half of a ring
  6. 7. Line segment joining two points on a circle