If P + Q means P is the sister of Q, P - Q means P is the brother of Q, and P × Q means P is the mother of Q, what is the relationship of R if P + R - Q?

B. R IS THE SISTER OF Q

A is the brother of B. C is the sister of B. D is the mother of A. How is D related to C?

B. MOTHER

P is the daughter of Q. R is the son of S, who is the sister of Q. How is S related to P?

A. AUNT

M is the grandmother of N. N has a brother O. What is M's relation to O?

B. GRANDMOTHER

T is the son of U. V is the daughter of U. W is the brother of T. How is W related to V?

B. BROTHER