I don't get anymore wetter, no matter how much rain falls on me.

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

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

I was born in a small house and I live in it all alone. No windows and no doors have been assigned to my house. The only way I can go out is by breaking through the walls of my house.

Who am I?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

What begins with T, ends with T, and has T in it?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

You have a basket containing ten apples. You have ten friends, who each desire an apple. You give each of your friends one apple.
Now all your friends have one apple each, yet there is an apple remaining in the basket.
How?

Prove that twice of ten is the same as twice of eleven.

A donkey is behind another donkey
I'm behind that second donkey
But there is a whole nation behind me

It is a murder you can describe in a word.