$A$ 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 $F$?

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 $B$?

$A$ 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 many nephews does $F$ have?

Introducing Rajesh,Neha said,"His brother's father is the only son of my grandfather." How is Neha related to Rajesh?

Following questions are based on the information provided below:
$A \times B$ means $A$ is mother of $B$.
$A - B$ means $A$ is brother of $B$.
$A + B$ means $A$ is sister of $B$.
$A \div B$ means $A$ is father of $B$.
How is $K$ related to $M$ in $R \div M - K$?

$A$ 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 is definitely a group of male members?