All the six members of a family $A, B, C, D, E$ and $F$ are travelling together. $B$ is the son of $C$ but $C$ is not the mother of $B$. $A$ and $C$ are a married couple. $E$ is the brother of $C$. $D$ is the daughter of $A$. $F$ is the brother of $B$. How many male members are there in the family?

If $A * B$ means $A$ is the mother of $B$; $A + B$ means $A$ is the brother of $B$; $A \times B$ means $A$ is the son of $B$ and $A - B$ means $A$ is the daughter of $B$,which of the following means $C$ is the niece of $D$?

$A$ is $B$'s sister. $C$ is $B$'s mother. $D$ is $C$'s father. $E$ is $D$'s mother. Then,how is $A$ related to $D$?

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 $F$. How is $D$ related to $F$?

$A + B$ 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 $P + R \div Q$,which of the following is true?

$P$ is the son of $Q$,while $Q$ and $R$ are sisters. $T$ is the mother of $R$. If $S$ is the son of $T$,which of the following statements is correct?