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

Can you spot the hidden girl in the picture below?

How many words can a pen with half refill write?

There was a man he lives in a hotel each morning he presses the first floor button each evening if there is a person in the elevator he asks him to press the 10 floor button if there is no one in the elevator he takes the stairs why.

What do you think with the below Picture ?

Can you count the number of squares in the figure below?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

In the image given, you can find several triangles. Can you count them all?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.