\item \lect
Given the following execution word $w$ of a Kripke structure. Evaluate the
formula $\varphi$ on $w$. Evaluate each sub-formula for any execution step using the
provided table.
\begin{itemize}
    \item $w = \{\}, \{a\}, \{a\}, \{b\}, \{\}, \{a\}, \{a, b\}^\omega$
    \item  $\varphi = \nex a \lor a \unt b$
\end{itemize}

  \begin{ltltabular}{7}
    \ltlSteps{6}{1}
    \ltlTrace{a}{0|1|1|0|0|1 |1}
    \ltlTrace{b}{0|0|0|1|0|0 |1}
    \hline
    \hline
    \ltlFormula{$\nex a$}
               {\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}}
    \ltlFormula{$a \unt b$}
               {\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}}
    \ltlFormula{$\nex a \lor a \unt b$}
               {\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}|\ws{1cm}}
  \end{ltltabular}