Consider 8 distinguishable playing cards, namely the 4 distinguishable Aces and the 4 distinguishable Kings. This set of 8 cards is distributed uniformly at random among 4 distinguishable players, called a, b, c, d such that each player gets exactly two cards. Player a sees that they have the Ace and King of hearts. From player a’s perspective (that is, knowing player a’s cards) what is the probability that player b has the ace and the King of diamonds?