If two's company, and three's a crowd, then whats four and five ?

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

Mother's Name is Mrs. SIXTY TWO
Son's Name is FIFTY TWO
Daughter's Name is FORTY TWO
What is Name of Father?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?

What am I?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

What does below pictogram mean?

I have eight fingers and two thumbs but I do not live. What Am I?

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?