Let's work on the UScereal dataset in the package UsingR, which contains $65$ samples and $11$ variables.

$($a$)$ Replace the levels of the factor variable $mfr$ to their full names, i$.$e$."G"$ for General Mills, $"K"$ for Kelloggs, $"N"$ for Nabisco, $"$P$"$ for Post, $"$Q$"$ for Quaker Oats, and $"R"$ for Ralston Purina.

Make a bar plot of the resulting correlationes in part $($a$)$ and arrange the nutrition facts in decreasing order in terms of their correlation with the calories. Which nutrition fact has the highest values?