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

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Two men play a dice game involving roll of two standard dice. Man X says that a 12 will be rolled first. Man Y says that two consecutive 7s will be rolled first. The men keep rolling until one of them wins.

What is the probability that X will win ?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

Which part of London exists in France as well ?

If we change the South-East direction into North and North-East into West and all others similarly.
Can you find out which direction will be in the place of South-West direction?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?