For Dad: a math puzzle

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Across
  1. 2. 90°
  2. 5. order of operations
  3. 7. how many health points a wither has
  4. 8. >180° but <360°
  5. 9. pre-
Down
  1. 1. 180°
  2. 3. the maximum number of bones it will take to tame a Minecraft wolf
  3. 4. 360°
  4. 6. how many health points a Minecraft person has
  5. 7. how many health points are in a heart in Minecraft