If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

What is red and smells like blue paint?

A newspaper is supposed to have 60 pages, but pages 24 and 41 are missing.
Which other pages won't be there?

Solve the equation by replacing the alphabet with numbers.

MOM + MOM + NO = BOOK=

What has no start, end, or centre?

A man escapes from jail using help from his girlfriend. The investigators suspect four girls of being the man's girlfriend.

Out of those four girls, one is his girlfriend who is lying. Two of the girls are completely innocent and are speaking the truth. One of the girls is the man's sister who is helping the girlfriend lie. Following are the statements from all four of them:

Ariana: "Myrna is his girlfriend."
Jane: "Angelina is lying."
Angelina: "Ariana is lying."
Myrna: "Jane is not his sister."

Can you find out who is the man's sister among them?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

I have eight fingers and two thumbs but I do not live. What Am I?

There are hundred red gems and hundred blue gems. The blue gems are priceless while the red gems equal wastage. You have two sacks one labeled Heads and the other Tails. You have to distribute the gems as you want in the two sacks. Then a coin will be flipped and you will be asked to pick up a gem randomly from the corresponding sacks.

How will you distribute the gems between the sacks so that the odds of picking a Blue gem are maximum?

How can a man go eight days without sleep?