Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

What has no start, end, or centre?

There is a place where if I stand up straight, I will still be considered sideways.

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

How many triangles are there on the puzzle below?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

I cannot talk, but I always reply when spoken to. What am I?

A farmer and his neighbour once went to Emperor Akbar"s court with a complaint. "Your Majesty, I bought a well from him," said the farmer pointing to his neighbour, "and now he wants me to pay for the water."
"That"s right, your Majesty," said the neighbour. "I sold him the well but not the water!"?
The Emperor asked Birbal to settle the dispute. How did Birbal solve the dispute?