You can see it everyday, But cannot touch it at will. What is it?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

I start and end with 500 and carry a 5 in my heart. But I require the first letter and the first number to be complete. I am the name of a King.

Who am I ?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

A boy was locked in a room by some robbers. All that is in the room is a piano, a calendar, and a bed. The room is locked from the outside. What does he eat, drink, and how does he escape and get out?

Spot what is wrong here in below Picture?

Can you find out which number multiplied by itself will give the output as 12345678987654321?

In an interview, a boy was asked an unusual question 'How two persons sitting with a table in between them can't see each other?' He was unable to reply. Can you?

How many minutes are there in Feb 2017?

Note: The shortest answer is the correct answer.

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?