I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

I cannot talk, but I always reply when spoken to. What am I?

Can you solve the maths in the below-given picture equation?

What can you hold in your right hand, but never in your left hand?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

Which three-digit number, made of consecutive digits, like 567, is 2 less than a cube and 2 more than a square?

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

What 5-letter word typed in all capital letters can be read the same upside down?

Mr Black, Mr Gray, and Mr White are fighting in a truel. They each get a gun and take turns shooting at each other until only one person is left. Mr Black, who hits his shot 1/3 of the time, gets to shoot first. Mr Gray, who hits his shot 2/3 of the time, gets to shoot next, assuming he is still alive. Mr White, who hits his shot all the time, shoots next, assuming he is also alive. The cycle repeats. If you are Mr Black, where should you shoot first for the highest chance of survival?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?