If P - Q means P is the mother of Q, Q + R means Q is the sister of R, and R * S means R is the father of S, what is the relationship of P to S?

A. GRANDMOTHER

D is the daughter of E. F is the brother of E. How is F related to D?

A. UNCLE

If P - Q means P is the sister of Q, P + R means P is the mother of R, and R × S means R is the daughter of S, what is the relationship of Q to S in the expression P - Q + R × S?

B. Q IS THE DAUGHTER OF S

N is the grandfather of O. P is the father of O. How is N related to P?

B. FATHER

If N is the father of O and P is the son of O, what is the relationship of N to P?

A. GRANDFATHER