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

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

When a clock is observed, the hour hand is at a minute mark and the minutes hand is six minutes ahead of it.

When the clock is observed again after some time, the hour hand is precisely on a different minute mark and the minute hand is seven minutes ahead of it.

Can you calculate how much time has elapsed between the two observations?

A father's child, a mother's child, yet no one's son.

Who am I?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

What is the Surname of Barbie Doll?

how come the second man dies?

4 fathers, 2 grand-fathers and 4 sons went to watch the movie.What is the minimum number of tickets they need to buy ?

Can you replace the question mark with the correct number in the below table sequence?

Decode the below four famous ciphers:

8P of the SS
1M of the E
1S of the SS
60M in 1H