Introducing a man,a woman said,'His wife is the only daughter of my father'. How was that man related to the woman?

$A \div B$ 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 $P \times R \div Q$,which of the following is true?

$X$ told $Y$,"Though $I$ am the son of your father,you are not my brother". How is $X$ related to $Y$?

Lakshmi and Meena are Rohan's wives. Shalini is Meena's step-daughter. How is Lakshmi related to Shalini?

There is a family of six persons $A, B, C, D, E,$ and $F$. They are lawyer,doctor,teacher,salesman,engineer,and accountant. There are two married couples in the family. $D$,the salesman,is married to the lady teacher. The doctor is married to the lawyer. $F$,the accountant,is the son of $B$ and brother of $E$. $C$,the lawyer,is the daughter-in-law of $A$. $E$ is the unmarried engineer. $A$ is the grandmother of $F$. What is the profession of $A$?

$A$ girl introduced a boy as the son of the daughter of the father of her uncle. The boy is the girl's: