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Multiple ChoiceBeginner 30s

undefined vs null

Choose the best answer for: uninitialized vs intentional absence
Options
  1. 1undefined is an object type while null is a number type in the spec
  2. 2undefined and null are completely identical values in every check
  3. 3null means an undeclared variable that has not been assigned yet
  4. 4undefined means not assigned; null means intentionally empty

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