26. A deck of 52 playing cards, containing all 4 aces, is randomly divided into 4 piles of 13 cards each. Define events E1, E2, E3, and E4 as follows:

:

1 E₁ = {the first pile has exactly 1 ace}, E2 = {the second pile has exactly 1 ace}, E3 = {the third pile has exactly 1 ace}, E4 = {the fourth pile has exactly 1 ace}