$A$ is the son of $B$; $C$,$B$'s sister,has a son $D$ and a daughter $E$; $F$ is the maternal uncle of $D$. How is $E$ related to $F$?

There is a family of six persons $A, B, C, D, E,$ and $F$. They are a 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 $F$. How is $D$ related to $F$?

Study the following information carefully to answer these questions.
$(i)$ $P \times Q$ means $P$ is brother of $Q$.
$(ii)$ $P - Q$ means $P$ is sister of $Q$.
$(iii)$ $P + Q$ means $P$ is father of $Q$.
$(iv)$ $P \div Q$ means $P$ is mother of $Q$.
Which of the following represents $M$ is nephew of $N$?

$A$ family consists of six members $P, Q, R, X, Y$ and $Z$. $Q$ is the son of $R$ but $R$ is not the mother of $Q$. $P$ and $R$ are a married couple. $Y$ is the brother of $R$. $X$ is the daughter of $P$. $Z$ is the brother of $P$. Who is the brother-in-law of $R$?

$I.$ $A, B, C, D, E$ and $F$ are six members of a family.
$II.$ One couple has parents and their children in the family.
$III.$ $A$ is the son of $C$ and $E$ is the daughter of $A$.
$IV.$ $D$ is the daughter of $F$ who is the mother of $E$.
Which of the following pairs are the parents of the children?

$A, B, C, D, E, F$ and $G$ are members of a family consisting of four adults and three children. Two of the children,$F$ and $G$,are girls. $A$ and $D$ are brothers and $A$ is a doctor. $E$ is an engineer married to one of the brothers and has two children. $B$ is married to $D$ and $G$ is their child. $A$ is the son of $C$. Who is $C$?