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

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

The sum of a mother, her baby and her dog's weight is 170 Kg. How much does the baby weigh if the mother weighs 100 kg more than the combined weight of the baby and the dog, and the dog weighs 60 per cent less than the baby?

There is something which is always coming but never arrives?

What begins with T, ends with T, and has T in it?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

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

Today, I celebrated my 32nd birthday but I was born in 1972.
How is this possible?