John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

What can go up a chimney down, but can’t go down a chimney up?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

What work can one never finish?

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

What occurs twice in a week, once in a year but never in a day?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

There is a circular car race track of 10km. There are two cars, Car A and Car B. And they are at the exact opposite end to each other. At Time T(0), Both cars move toward each other at a constant speed of 100 m/seconds. As we know both cars are at the same speed they will always be the exact opposite to each other.
Note, at the center, there is a bug which starts flying towards Car A at time T(0). When the bug reaches car B, it turns back and starts moving towards the car A. The speed of bug is 1m/second. After 5 hours all three stop moving.
What is the total distance covered by the bug?

There was a strange boy who was born before his father. How can this be possible?

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?