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

I have Rs.50 and I spend it in the way as below.

O_er_t_o_

Complete the missing letters of the given word.

Find the number of squares in the below picture

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

The following question it puts forth you:

25 - 55 + (85 + 65) = ?

Then, you are told that even though you might think it's wrong, the correct answer is actually 5!

Whats your reaction to it? How can this be true?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

John is pretty weird. He likes toffees but hates chocolates. He loves books but never reads. He likes to build his troops in an online game but does not proceed with the war. He likes to go swimming but is afraid of water.

Seeking this behaviour, can you tell whether he likes balloons and parties?