There is one thing that goes round the house and also inside the house but never even share a brief touch. What is it?

What are the 50th, 63rd and 100th numbers in the sequence below?
4, 5, 8, 8, 9, 9, 12, 13, 13, 13, 17, 18, ...

A maths symbol is hidden in the below Bar Graph. Can you decipher it?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Why do you find that most of the buildings are deprived of the 13th floor?

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

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

A woman is sitting in her hotel room and hears a knock at the door. She opens the door to see a man whom she’s never met before. He says, “I’m sorry, I have made a mistake, I thought this was my room.” He then goes down the corridor and into the elevator. The woman goes back into her room and calls security. What made the woman so suspicious of the man?

Solve the puzzle by telling what does below picture means.

There is a shop where written:
Buy 1 for $1
10 for $2
100 for $3
I needed 999 and still only paid $3. How could this be financially viable for the shop-keeper?