Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

What jumps when it walks and sits when it stands?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

Twice ten are six of us,

Six are but three of us,

Nine are but four of us;

What can we possibly be?

Would you know more of us?

Twelve are but six of us,

Five are but four, do you see?

What are we?

What is the centre of gravity?

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

Three ants are going up a hill, one behind the other. The last ant then says to the other ants, 'There is an ant behind me!'' How come?

People put me on the table and cut me but do not eat me. What am I?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

Given that

(78)^9 = 6
And (69)^4 = 11

Can you find out

(99)^2 =?

(Note: This is Logical, not Mathematical)