Using the str function, we saw that the League column stores a factor. You can corroborate this by using the class function on the League column.

class(Hitters$League)
#> [1] "factor"

The question of this exercise is how many types of leagues are included. For this question we will combine two functions, in a nested way, to determine the number of unique categories. Use the functions levels and length to determine the number of regions defined by this dataset and contained in Hitters$League.

NOTE

Do not forget to first load the data as in the previous exercises!