$D$ is $A's$ son. $C$ is the mother of $P$ and wife of $D$. How is $A$ related to $C$?

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 $R \div M - K$?

Rahul's mother is the only daughter of Monika's father. How is Monika's husband related to Rahul?

In a family,there are six members $A, B, C, D, E$ and $F$. $A$ and $B$ are a married couple,$A$ being the male member. $D$ is the only son of $C$,who is the brother of $A$. $E$ is the sister of $D$. $B$ is the daughter-in-law of $F$,whose husband has died.
How is $F$ related to $A$?

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 $D$?

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