What's the only room from which no one can enter or leave

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

If 24H in a D => 24 hours in a day.
What does "64S on CB" stand for?

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

In order to complete the racing competition, the Mexico racetrack has to submit its top and the most famous three horses to win the competition. Due to an electrical storm, all the records are cleared and no one knows which horse holds the record. They all look identical and it becomes even more difficult to differentiate the horses. There are 25 horses in the Mexico racetrack. But there can be only five horses at a time on the track. What will the least number of races that can be conducted to find out the three fastest horses?

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

Find the last number in the series below:

voN luJ yaM raM ---

A man was just doing his job when his suit was torn. Why did he die three minutes later?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

One evening there was a murder in the home of a married couple, their son and daughter. One of these four people murdered one of the others. One of the members of the family witnessed the crime.

The other one helped the murderer.

These are the things we know for sure:

1. The witness and the one who helped the murderer were not of the same sex.

2. The oldest person and the witness were not of the same sex.

3. The youngest person and the victim were not of the same sex.

4. The one who helped the murderer was older than the victim.

5. The father was the oldest member of the family.

6. The murderer was not the youngest member of the family.

Who was the murderer?