$A$ is the father of $C$,and $D$ is the son of $B$. $E$ is the brother of $A$. If $C$ is the sister of $D$,how is $B$ related to $E$?

If $X \circ Y$ means $X$ is the wife of $Y$,$X \cdot Y$ means $X$ is the son of $Y$,and $X * Y$ means $X$ is the sister of $Y$,which of the following would mean that $A$ is the daughter of $B$?

$A$ boy goes to see a film and finds a man who is his relative. The man is the husband of the sister of his mother. How is the man related to the boy?

$A + B$ means $A$ is the son of $B$; $A - B$ means $A$ is the wife of $B$; $A \times B$ means $A$ is the brother of $B$; $A \div B$ means $A$ is the mother of $B$; and $A = B$ means $A$ is the sister of $B$.
What does $P \times R \div Q$ mean?

If $A + B$ means $A$ is the sister of $B$,$A - B$ means $A$ is the brother of $B$,and $A \times B$ means $A$ is the daughter of $B$,which of the following shows the relation that $E$ is the maternal uncle of $D$?

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 $A$?