Can you convert the number zero(0) into a positive number using just one mathematical operator ?

What is the next number in this matchsticks series riddle?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

Can you count the number of quadrilaterals in the picture below?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

Make a sentence consisting of three words that have the whole alphabet.

Role Action
Block Prevents the target player from acting
Redirect Change target player target.
Save Protects the target player from death.
Seer Sees all actions that occurred
Murderer Kills the target player

The following five players are playing:

Andy
Brian
Chris
Daniel
Fred

You are Andy the Seer and you saw the following things:
a) Brian was redirected to Chris.
b) Chris was blocked.
c) Daniel was killed.

Who is the murderer then?

What Deficiency does the below rebus represent?

VIT_MIN

There was a kingdom in which the king had no heir to take over his thrown. Even the queen was dead and he himself was on the verge of dying. He thought about it and then summoned all of the teenagers. He gave one seed each to all of them and asked them to grow the plant. He announced that the one with the most beautiful plant will become the king/queen of the empire after the death of the king.

After a month, all of them were called. The king looked at all of the plants but announced the girl with an empty pot as the queen of the empire. Why?