Răspuns:
1 b; 2 c; 3 c; 4 b; 5 c; 6 a; 7 c; 8 b; 9 c; 10 b; 11 b; 12 a; 13 c; 14 a; 15 b; 16 b; 17 a; 18 c; 19 b; 20 b.
