MCQ on ring theory 1. (Z,+,•) is ? (1 point) ◯ field ◯ Ring ◯ integral domain ◯ Ring and integral domain 2. A integral domain is field if________ (1 point) ◯ finite ◯ infinit 3. If in a ring with unit (xy)²=x²y² ∀x,y∈R,then, (1 point) ◯ R is commutative ring ◯ R is an integral domain ◯ R is a field ◯ Not of this 4. Which of following is not a ring? (1 point) ◯ (N,+,•) ◯ (Z,+,•) ◯ (Q,+,•) ◯ (R,+,•) 5. In a ring (R,+,•) which of following is correct? (1 point) ◯ (a+b)²⁼a²+ab+ba+b² ◯ (a+b)(a-b)=a²-ab+ba-b² ◯ Both (a) and (b) correct ◯ Both (a)&(b) are not correct ...