Can you find out the next digit in the following series ?

0, 0, 1, 3, 2, 6, 3, 9, 4, 12, 5, ?

You walk into a room where there are three primates held in their respective cages:
1) A lion who is eating the flesh of a goat.
2) An orangutan who is playing with blocks.
3) A donkey who is sitting idle.

Who is the most intelligent primate in the room?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

Prove that twice of ten is the same as twice of eleven.

I am lying and I always lie. Tell me whether I am lying or telling the truth.

In the picture given below, can you find out which digit will take place of the question mark?

What does this below rebus puzzle mean?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

In the picture, you can see a chess board. On the top left position, the K marks a knight. Now, can you move the knight in a manner that after 63 moves, the knight has been placed at all the squares exactly once excluding the starting square?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?