What is the coolest letter in the alphabet?

Can anyone tell me a word in the English dictionary which has a silent 'z'?

If your uncle’s sister is not your aunt, what relation is she to you?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

Trying to tease Birbal, Akbar gave him one gold coin and ask him to buy
* something for him to eat
* something for him to drink.
* something to feed the cows
* something to plant in the garden
and most important you need to buy only one thing.

What must Birbal buy to silence Akbar?

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

Our product and our sum always give the same answer. Who are we?

Solve the equation in the image by looking at the pattern closely.

What does this mathematical rebus means ?

Can you find out who is the kidnapper in below Picture and why, Explain ?