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

There is a movie name hidden in the picture that is attached with this question. Can you find out which movie is it?

What has hands, but can’t clap?

Client Dempsey living in one of the East Coast states of the U.S. was talking to Landon Donovan, who was living in the West Coast state of the U.S.

Dempsey: What time is it?
Donovan: Wow, It is the same time here.

How is this possible?

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?

What is the centre of gravity?

You are given 2 eggs.
You have access to a 100-storey building.
Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor, Both eggs are identical.
You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.
Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

Can you find out the number that should replace the question mark with a valid reason?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

What number should come in place of the question mark below?