Răspuns: a) C=( 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19)
b) card A=4 card B= 4
c) AUB ={0,1,2,3,4,5}
d) AПC={0,1,2,3,}
e) B-C= O ( taiat)
f) C-B U(invers) A={0,1}
Explicație pas cu pas: