%%
%% The LaTeX Companion, 3ed
%%
%% Example 3-3-39 on page I-177 in "Controlling printing".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{135.0pt}

  \setlength\parindent{0pt}
  \setlength\parskip{2pt}

%StartShownPreambleCommands
\usepackage{siunitx}
\DeclareSIUnit[per-mode=symbol]\kmh{\kilo\metre\per\hour}
\newcommand\sample[1]{\textnormal{\noindent #1:}
        The speed limit is \qty{100}{\kmh}.\par}
%StopShownPreambleCommands

\begin{document}
\sffamily    \sample{A}     \textbf{\sample{B}}
\sisetup{text-family-to-math,text-series-to-math}
\sample{C}   \textbf{\sample{D}}
\sisetup{mode=match,reset-text-family=false,
        reset-text-series=false}
\textbf{\sample{E}}
\end{document}
