What is the next number in the series?

15 29 56 108 208 ?

What is both possible and impossible at the same time?

What is the Surname of Barbie Doll?

How many minutes are there in Feb 2017?

Note: The shortest answer is the correct answer.

You stand in front of two doors. A guard stands next to each door. You know the following things: one path leads to paradise, the other leads to death. You cannot distinguish between the two doors. You also know that one of the two guards always tells the truth and the other always lies. You have permission to ask one guard one question to discover which door leads to paradise. What one question would you ask to guarantee you enter the door to paradise?

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

Give it food and it will live; give it water and it will die.

What do you call a fish without an eye?

Why do you find that most of the buildings are deprived of the 13th floor?