If the regular set $$A$$ is represented by $$A = {\left( {01 + 1} \right)^ * }$$ and the regular set $$'B'$$ is represented by $$B = \left( {{{\left( {01} \right)}^ * }{1^ * }} \right),$$ which of the following is true?

Which of the following sets can be recognized by a Deterministic Finite-state Automation?

The string $$1101$$ does not belong to the set represented by

How many substrings of different lengths (non-zero) can be formed from a character string of length $$n$$ ?