What has to be broken before you can use it?

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

A boy and his father are caught in a traffic accident, and the father dies. Immediately the boy is rushed to a hospital, suffering from injuries. But the attending surgeon at the hospital, upon seeing the boy, says 'I cannot operate. This boy is my son.' How is this situation explained?

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Why is the Hole below a Lock?

Two natural numbers have a sum of less than 100 and are greater than one.

John knows the product of the numbers and Jacob knows the sum of numbers.

The following conversation takes place between them:
John: 'I am not aware of those numbers.'
Jacob: 'I knew you wouldn't be. I am not aware myself.'
John: 'Now I know them!'
Jacob: 'Now I know them, too!'

What are the two numbers?

who is silent in the parliament?

What do you answer even though it never asks you questions?

In the given picture, in how many ways can you read the word "Tiger"?

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