ps://ggplot2.tidyverse.org/reference/ggtheme.html" class="external-link">theme_bw</a></span><span class="op">(</span><span class="op">)</span> <span class="op">+</span> </span>
<span>  <span class="fu"><a href="https://ggplot2.tidyverse.org/reference/facet_grid.html" class="external-link">facet_grid</a></span><span class="op">(</span><span class="va">mpg</span><span class="op">&gt;</span><span class="fl">20</span><span class="op">~</span><span class="va">.</span>, labeller <span class="op">=</span> <span cl