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

It is a six-letter word.
The first four letters are me.
The second and last letters are the same.
The fourth second and last letter is payment.

Who is it?

There is a basket full of hats. Three are white and two are black. Three men, Tom, Tim, and Jim, each take a hat out of the basket and put it on their heads without seeing the hat they selected or the hats the other men selected. The men arrange themselves so Tom can see Tim and Jim’s hats, Tim can see Jim’s hat, and Jim can’t see anyone’s hat. Tom is asked what color his hat is and he says he doesn’t know. Tim is asked the same question, and he also doesn’t know. Finally, Jim is asked the question, and he does know. What colour is his hat?

What is both possible and impossible at the same time?

Which is the correct shadow of the bird?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

You can hear me, but you can't touch or see me.

What am I?

Find the missing number in the image below.

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?