I’m tall when I’m young, and I’m short when I’m old. What am I?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

If you're 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door?

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

Using eight eights and addition only, can you make 1000?

I never was there, I am always to be.
You have never ever seen me, not ever you will.
Yet I am the confidence of everyone.

Who Am I?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

What will you call your mother's brother's brother-in-law?

If "P" means "-", "Q" means "/", "R" means "+", and "S" means "*" then find the value of the following:

21 Q 7 R 9 S 10 P 13

In a jungle where there are no street lights or any other artificial source of lights, I notice a black snake crossing the road.
How did I get sight of the snake?