Name a key which is hardest to turn.

You can win me and lose me but never buy me
You can not eat me and never want to part with me
I can make you cry or bring you joy
I am not a machine and definitely not a toy
You keep me but i am not forever just yours
You might find me in a case or on a shelf next to a vase
I am hard and i am tall if you bump me i am sure to fall
I am made of different materials and am at many events
If your lucky and fight hard I might be yours
What am I ?

Can you count the number of blocks in the picture below?

What do you call a fish without an eye?

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

Can you guess the name of the month by looking the below rebus ?

10+10 and 11+11 can give you the same answer.

Explain how?

Move four matchsticks to the below square to form three squares?

You have four chains. Each chain has three links in it. Although it is difficult to cut the links, you wish to make a single loop with all 12 links. What is the fewest number of cuts you must make to accomplish this task?

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

How can this be possible?