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Tell whether each of the following are recursive, RE-but-not-recursive, or non-RE.

1. The set of all $TM$ codes for $TM's$ that halt on every input.
2. The set of all $TM$ codes for $TM’s$ that halt on no input.
3. The set of all $TM$ codes for $TM's$ that halt on at least one input.
4. The set of all $TM$ codes for $TM's$ that fail to halt on at least one input.
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