what does the below rebus means?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

Take one out and scratch my head, I am now black but once was red. What am I?

John was piloting a plane behind a car but was never able to overtake it. Why?

There are 3 apples in the basket and you take away 2. How many apples do you have now?

A man dies of old age on his 25 birthday. How is this possible?

The sum of a mother, her baby and her dog's weight is 170 Kg. How much does the baby weigh if the mother weighs 100 kg more than the combined weight of the baby and the dog, and the dog weighs 60 per cent less than the baby?

French Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead man who obviously hung herself from the ceiling, but they are not able to figure out how this had happened.

John and Jacob entered the crime scene and easily able to solve the case.

How did the man die?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?