What is full of holes but still holds water?

I travel all around the world but always stay in the corner. What am I?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

What does the below rebus riddle means?

How many runs at maximum can a batsman score in a normal one-day match? Consider the fact that the conditions are ideal and there are no No Balls, no Wide Balls and no Extras in that match.

You are trapped in a room with two doors. One leads to certain death and the other leads to freedom. You don't know which is which.
There are two robots guarding the doors. They will let you choose one door but upon doing so you must go through it.
You can, however, ask one robot one question. The problem is one robot always tells the truth, the other always lies and you don't know which is which.
What is the question you ask?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

Can you count the number of squares in the given picture?

What does this simple rebus mean?