Find out the number of circles in the given picture having Illusion

There is a jar in which there are two types of candies.
20 blueberries and 16 strawberries. You perform the following steps:
1) You take out two candies.
2) If the two candies are of the same flavour, you add a blueberry one otherwise, you add the strawberry one.

You repeat these two steps till there is just one candy remaining in the jar. Which flavoured candy will be left?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?

What is the Surname of Barbie Doll?

John was piloting a plane behind a car but was never able to overtake it. Why?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

Where do fish keep their money?

Solve the alphametic puzzle by replacing the alphabet with the number.

S T O R M +
S O L E S
=========
T O W E L
=========

I am a five-letter word under you,
Remove the first letter and I am above you,
Remove the second as well and I am around you.

Who am I?

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