What does this rebus mean?

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The below given figure comprises of a pattern through which you can determine the missing letter. Can you push your mind to find the pattern and add the missing letter?

Rebus Puzzle Definition: A rebus is an illusion device that uses pictures to represent words or parts of words.
What does This Rebus Puzzle Identify?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

A man has to get a fox, a chicken, and a sack of corn across a river.

He has a rowboat, and it can only carry him and one other thing.
If the fox and the chicken are left together, the fox will eat the chicken.
If the chicken and the corn are left together, the chicken will eat the corn.

How does the man do it?

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?

Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

Using eight eights and addition only, can you make 1000?

Can you fill the blank with the correct number?

6 30 870 756030 _____

1 + 9 + 8 = ?
considering, 28 + 8 + 92 = 10