$A$ and $B$ both are children of $C$. If $C$ is the mother of $A$,$A$ is the son of $C$ but $B$ is not the daughter of $C$,how are $A$ and $B$ mutually related?

$A$ and $B$ are a married couple. $X$ and $Y$ are brothers. $X$ is the brother of $A$. How is $Y$ related to $B$?

Pointing to a lady on the platform,Anju said,'She is the sister of the father of my mother's son'. Who is the lady to Anju?

$A \div B$ means $A$ is the father of $B$,$A - B$ means $A$ is the wife of $B$,$A \times B$ means $A$ is the brother of $B$,$A + B$ means $A$ is the daughter of $B$.
If $P \div R + S + Q$,which of the following is true?

$A$ and $B$ are brothers,$C$ and $D$ are sisters. $A$'s son is $D$'s brother. How is $B$ related to $C$?

$A$ family consists of six members $P, Q, R, S, T$ and $U$. There are two married couples. $Q$ is a doctor and the father of $T$. $U$ is the grandfather of $R$ and is a contractor. $S$ is the grandmother of $T$ and is a housewife. There is one doctor,one contractor,one nurse,one housewife,and two students in the family. Which of the following are the two married couples?