Suppose in Exercise 26 we had defined the events Ei = 1, 2, 3, 4, by
E1 = {one of the piles contains the ace of spades},
E2 = {the ace of spades and the ace of hearts are in different piles},
E3 = {the ace of spades, the ace of hearts, and the ace of diamonds are in different piles},
E4 = {all 4 aces are in different piles}