It is always ahead of me yet I can never see it. What is it?

There was a blind man. He had four socks in his drawer either black or white. He opened it and took out two socks. Now the probability that it was a pair of white socks is 1/2.

Can you find out the probability that he had taken out a pair of black socks ?

You know three triplets: Frank John and Wayne (need to return your money). Frank always tells the truth while John and Wayne always lie. You meet one of them on the road and can ask him a three-word question.
Which question, will you ask?

I hide my treasure in the ground, my tail is big and fluffy. If you spot me in a tree, please don’t call me scruffy. What am I?

What do you see in the given picture?

I don't get anymore wetter, no matter how much rain falls on me.

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

Find the value of "?" in the ball picture Riddle below:

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?