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Examine the formal definition of a Turing machine to answer the following questions, and explain your reasoning.

  1. Can a Turing machine ever write the blank symbol $\sqcup$ on its tape?
  2. Can the tape alphabet $\Gamma$ be the same as the input alphabet $\Sigma$?
  3. Can a Turing machine’s head ever be in the same location in two successive steps?
  4. Can a Turing machine contain just a single state? 

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