Be active and find the killer in the picture Riddle below.

Find the 8 in the below-given Image.

No matter how little or how much you use me, you change me every month. What am I?

Find the smallest sentence with all the English alphabet.

A gardener planted the Lemon trees in a mathematical ordered way (i.e. he planted a tree in rows).
He created a total of 19 rows of trees.

Note: There should be more than 2 trees to count as a row.

What is the minimum number of trees required by the gardener to have 19 rows of trees?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

Can you name an animal whose killing cannot be performed without spilling your own blood?

What kind of band never plays music?

This was asked in an interview with Coa-Cola.

The interviewer has given me 100 marbles(50 white and 50 black) and two empty boxes.
He then told me that he will leave the room and i need to place all the marbles in two boxes.

And When he come back, he will draw a marble from any of the two box and if the marble is white I will be hired.

Also
* No box can be empty.
* All 100 marbles must be placed in one of the two boxes.

So what should I have done?

In the Chess Board picture below white army is arranged. You need to add a black army on the board such that no piece is under any threat.
Note: Army comprised of 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns.