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

What is the largest amount of money that you can possess in change and still if someone asks you for a dollar, you won't be able to give?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

What does this mean?

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Can you find the hidden animal in the picture below?

Birbal was jester, counsellor, and fool to the great Moghul emperor, Akbar.
The villagers loved to talk of Birbal's wisdom and cleverness,
and the emperor loved to try to outsmart him.
One day Akbar (emperor) drew a line across the floor.
"Birbal," he ordered, "you must make this line shorter, but you cannot erase any bit of it."
Everyone present thought the emperor had finally outsmarted Birbal.
It was clearly an impossible task.
Yet within moments the emperor and everyone else present had to agree that Birbal had made the line shorter without erasing any of it.
How could this be?

How can you leave a room with two legs and return with six legs?

Can you Find and name the hidden bird in the picture below ?

Replace the question mark with the correct number in the below-given picture?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?