If Kamal says,"Ravi's mother is the only daughter of my mother," how is Kamal related to Ravi?

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

$A \div B$ 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?

$A$ 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 $A + B$ means $A$ is the brother of $B$; $A \cdot B$ means $A$ is the father of $B$ and $A \times B$ means $A$ is the sister of $B$,which of the following means $M$ is the uncle of $P$?

There are six children playing football namely $A, B, C, D, E$ and $F$. $A$ and $E$ are brothers. $F$ is the sister of $E$. $C$ is the only son of $A$'s uncle. $B$ and $D$ are the daughters of the brother of $C$'s father. How many male players are there?