What does this rebus mean?

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

What part of the chicken has the most feathers?

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

As we know that white starts the game of chess. Can you find the scenario shown in the picture below is possible when all the white pieces are at the original place while the black pawn is not as in the below picture?

I always drive my customer away.

Who am I?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

I can write cow in 13 letters.

Can You?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

Solve the mathematical equation in the picture below.