What do you answer even though it never asks you questions?

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

What number divided by 4 is the same as that number minus 4?

I organized a small get together at my home.
In the party , i have a barrel with some whiskey in it.

Suddenly Guest 1 say 'I bet this barrel of whiskey is more than half full'.
'No, it's less than half full' Guest 2 replied.

I don't have any measuring instrument and without removing whiskey from it , how can i determine which of the guest is right ?

What is red and smells like blue paint?

A man says, "Brothers and sisters, have I none, but that man's father is my father's son." Who is that man?

I have Rs.50 and I spend it in the way as below.

Why do we preferably have round manhole covers and not square ones?

All of Jacob's shoes are red except two.
All of Jacob's shoes are green except two.
All of Jacob's shoes are yellow except two.

How many shoes does Jacob have?

What does this rebus riddle means ?