Răspuns:
A) A={ 1, 2 ,3 ,4} ,,, card A= 4
B) B={ 3, 4 ,5, 6} ,,, card B= 4
C) C={ 3, 6, 9} ,,, card C=3
D) D={ 6, 8, 10, 12} ,,, card D= 4
