```r
ggplot(martian.df[martian.df$Site == "Site I",], aes(x = Height, y = Speed.Mars)) +
geom_point(col = "#F5B319", alpha = 0.6) +
scale_x_continuous("Height (cm)", limit = c(180, 220), expand = c(0, 0)) +
scale_y_continuous("Running time (s)", limit = c(16, 28), expand = c(0, 0)) +
  stat_smooth(method = "lm", se = FALSE, col = "#C42126") +
theme(legend.position = c(0.8, 0.8),
      panel.background = element_blank(),
      panel.grid.major = element_blank(),
      panel.grid.minor = element_blank(),
      axis.ticks.x = element_line(colour = "black"),
      axis.ticks.y = element_line(colour = "black"),
      axis.text.x = element_text(colour = "black"),
      axis.text.y = element_text(colour = "black"),
      axis.line = element_line(colour = "black")
)
```

<div class="figure" style="text-align: center">
<img src="figures/graphics-Martianlinreg1-1.png" alt="Time to run 100m versus Martian height and the associated OLS solution (red line)." width="359.05536" />
<p class="caption">(\#fig:Martianlinreg1)Time to run 100m versus Martian height and the associated OLS solution (red line).</p>
</div>