How can you make number one disappear by adding something to it?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

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

Which Travels Faster? Solve below famous picture riddle:

What can you deduce from the following BrainBat?

CRY
LMKI

A very interesting trivia question for all.

Why do men's shirts have their buttons on the right side and women's have buttons on the left-hand side?

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.

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?