Complete the table series riddle by finding the number that can replace "??".

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

In the city of Brain Teasers, 5% of people do not list their phone numbers. Now if we select random 100 people from the phone directory, then how many people selected will have unlisted phone numbers?

What word is pronounced the same if you take away four of its five letters?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside. The man said, "Oh! I am really sorry, I thought this was my room." He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man. What made her suspicious of that man? He might have been genuinely mistaken.

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

A quarter is one-fourth of a dollar but Mr. John has changed the equation as below :

DOLLAR * 4 = QUARTER

Can you replace each letter with a digit to make the above solution correct?

Complete the series by replacing "?" with the correct number.

ST ND RD TH '?'

Below rebus represent famous DiCaprio movie. Can you name it?

You are offered an opportunity to win a fortune. There are 100 precious black stones and 100 unworthy white stones. There are two different sacks labelled as "Heads" and "Tails". You can distribute the stones as you wish. Then a coin will be flipped. Then you will have to choose a stone from the corresponding sack. If you pick up a black stone, all the fortune of black stones is yours but if you pick up white, you get nothing.

How will you distribute the stones so that you can maximize your chances of winning?