A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?

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.

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

There was a man he lives in a hotel each morning he presses the first floor button each evening if there is a person in the elevator he asks him to press the 10 floor button if there is no one in the elevator he takes the stairs why.

I have an eye but still cannot see.

Who am I?

On 26-01-2022, Juli was murdered at her house in a city in India in the afternoon. There were three suspects in the murder and the following are the statements that were given by them:

John: I visited my village that day.
Jacob: I was out to deposit my house tax in the municipality office at that time.
Jonny: I was at a friend's place having lunch at that time.

Can you find out who is the murderer?

Rearrange the letters in "new door" to make one word.

What does this mathematical rebus means ?