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?

How many times can you subtract the number 5 from 25?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

If six children and two dogs were under an umbrella, how come none of them got wet?

Can you write down eight eights so that they add up to one thousand?

If eleven plus two equals one, what does nine plus five equal?

What does the following BrainBat signifies?

ABCDEFGHIJKLMNOPQRSTUVWYZ

QQQQQQQQQQQQQQQQQQQQQQQQQ.

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

I am the fastest animal but cannot climb the tree. What am I?