You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

You were playing ping pong with your friend. Suddenly the ball fell into a narrow metal pipe that was imbedded in the concrete surface of the floor one foot deep. Now you don't have any other ball and you desperately want to take it out and play. You and your friend have your shoelaces, your tennis paddle and a plastic water bottle. However, the bottle cannot fit into the pipe.

How will you take the ball out?

There is a movie name hidden in the picture that is attached with this question. Can you find out which movie is it?

You throw me out when you want to use me and you take me in when you don't want to use me.

Who Am I?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

A man dies of old age on his 25 birthday. How is this possible?

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.

What does the below mathematical rebus mean?