I have teeth but i don't bite. Who Am I ?

Which word does the below Plexor means ?

There are six people in a family namely M, N, O, P, Q and R.

R and O are brother and sister.

N is the brother of Q's husband.
P is the father of M and grandfather of R.

How many male members are in the family?

Replace the question mark in the picture below.

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C

What can go up a chimney down, but can’t go down a chimney up?

A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks - so that each deck contains an equal number of face-up cards. Remember, you are blindfolded.

How will you do it?

What does this mean?

CCCCCCC

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

I make two people out of one. What am I?