There are 2r (2r = n) gloves randomly chosen from n distinct pairs of gloves (i.e., 2n gloves in total). Note that two gloves in the same pair are also different. Find the total number of ways such that
no gloves are paired in the 2r gloves.
there is exactly one pair of gloves in the 2r gloves.
there are exactly r pairs of gloves in the 2r gloves.
please explain your processes