In a coded relation, if M + N means M is the daughter of N, M - N means M is the son of N, and M × N means M is the grandmother of N, what is the relationship of O if M + O - N?
If A + B means A is the brother of B, A - B means A is the sister of B, and A × B means A is the father of B, what is the relationship of C if A + C - B?
In a coded relation, if A ÷ B means A is the daughter of B, B + C means B is the father of C, and C - D means C is the brother of D, what is the relationship of D to A?