%\texttt{\textbackslash textsuperscript} and
%\texttt{\textbackslash emph} macros, as illustrated (Table~\ref{tbl:notes}).

\begin{table}
\caption{Summary of the VEIN \textcolor{red}{S3 classes}.}
\label{ta:class}
\begin{tabular}{@{}llrrrrrrrrrr@{}}
\hline      %\toprule
Class  &  Units  \\ \hline %\midrule
{\tt Emissions} & $\mathrm{g \cdot h^{-1}}$    \\
{\tt EmissionsArray}$^a$ & $\mathrm{g \cdot h^{-1}}$\\
{\tt EmissionFactors} &	 $\mathrm{g \cdot km^{-1}}$ \\
{\tt EmissionFactorsList}$^a$ &	 $\mathrm{g \cdot km^{-1}}$   \\
{\tt EmissionsList} & $\mathrm{g \cdot h^{-1}}$    \\
{\tt Evaporative} &	$\mathrm{g \cdot day^{-1}}$ \\
{\tt Speed} & $\mathrm{km \cdot h^{-1}}$   \\ 
{\tt Vehicles} &		 $\mathrm{h^{-1}}$ \\ \hline %\midrule
\end{tabular}

%  \textsuperscript{\emph{a}} {\tt EmissionFactorsList} and {\tt EmissionsArray} do not show their units explicitly.
\textsuperscript{\emph{a}} Do not show their units explicitly.
%  \textsuperscript{\emph{b}} \textbf{Some more text}.
\end{table}


%\begin{table}
%\centering
%\caption{Summary of the VEIN classes.}
%\label{ta:class}
%\begin{tabular}{@{}llrrrrrrrrrr@{}}
%\hline      %\toprule
%Class  & Methods  & Units  \\ \hline %%\midrule
%{\tt Vehicles} &	print, plot, summary &	 $\mathrm{h^{-1}}$   \\
%{\tt EmissionFactors} &	print, plot, summary  &	 $\mathrm{g \cdot km^{-1}}$ \\
%{\tt EmissionFactorsList}$^a$ &	print, plot, summary  &	 $\mathrm{g \cdot km^{-1}}$   \\
%{\tt Emissions} &	print, plot, summary  &	 $\mathrm{g \cdot h^{-1}}$    \\
%{\tt EmissionsArray}$^a$ &	print, plot, summary  &	 $\mathrm{g \cdot h^{-1}}$\\
%{\tt EmissionsList} &	print, plot, summary  &	 $\mathrm{g \cdot h^{-1}}$    \\
%{\tt Evaporative} &	print, plot, summary  &	 $\mathrm{g \cdot day^{-1}}$ \\
%{\tt Speed} &	print, plot, summary  & $\mathrm{km \cdot h^{-1}}$   \\ \hline %\midrule
%\end{tabular}

%  \textsuperscript{\emph{a}} {\tt EmissionFactorsList} and {\tt EmissionsArray} do not show their units explicitly.
%\textsuperscript{\emph{a}} Do not show their units explicitly.
%%  \textsuperscript{\emph{b}} \textbf{Some more text}.
%\end{table}