Răspuns:
1->fie n nr de 4 cifre
p. cif = n/1000
u. cif = n%10
2-> 8+4=12; 2+3=5; 1+40-0=41; 24-1=23
3-> L=2*l (cred)
4->x∈{ 4,5,6,7}
5->2,3,4,5
6-> TRUE; TRUE
7-> x<5; y==9; z<=3 AND x>6
