Which five letter word can be added at the end of below word to form a
valid word?

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The Little ant seems to be always confused. Do you know why?

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.

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

Why is the longest human nose just 11 inches?

In order to complete the racing competition, the Mexico racetrack has to submit its top and the most famous three horses to win the competition. Due to an electrical storm, all the records are cleared and no one knows which horse holds the record. They all look identical and it becomes even more difficult to differentiate the horses. There are 25 horses in the Mexico racetrack. But there can be only five horses at a time on the track. What will the least number of races that can be conducted to find out the three fastest horses?

How is a fly different from a mosquito?

A doctor and a boy were fishing. The boy was the doctor’s son, but the doctor was not the boy’s father. Who was the doctor?

I travel all around the world but always stay in the corner. What am I?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?