Shape Crossword Puzzle

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Across
  1. 2. Shape that takes up space. Is the subject.
  2. 4. One color, different values.
  3. 5. Shape that is the background, void.
  4. 6. The type of shape that is freeform, found in nature.
Down
  1. 1. Mathematical Shape
  2. 3. Element of art that is 2D.