Let's do a test:
Two students, Tom and Jack are doing a test. Professor Jhon has 16 playing cards, they are:
Hearts : A, Q, 4
spades : J, 8, 4, 2, 7, 3
Clubs : K, Q, 5, 4, 6
Dimonds: A, 5
Tom and Jhon know all these 16 playing cards. Professor Jhon picks up one card from these 16...