What breaks yet never falls, and what falls yet never breaks?

Your mother’s brother’s only brother-in-law is asleep on your couch. Who is asleep on your couch?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

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?

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

Your last good ping-pong ball fell into a narrow metal pipe embedded one foot deep in concrete.
How can you get it out undamaged, if all the tools you have are your tennis paddle, shoe laces, and plastic water bottle, which does not fit into the pipe?

If you toss a coin 10 times and it lands heads up every time, what are the chances it will land heads up if you toss it again?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

How many sides does a circle have?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?