What does this Rebus Picture means ?

You are an expert on paranormal activity and have been hired to locate a spirit haunting an old resort hotel. Strong signs indicate that the spirit lies behind one of four doors. The inscriptions on each door read as follows:

Door A: It's behind B or C
Door B: Its behind A or D
Door C: It's in here
Door D: It's not in here

Your psychic powers have told you three of the inscriptions are false, and one is true. Behind which door will you find the spirit?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

What is both possible and impossible at the same time?

What does this mean?

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Can you find the 09 errors in the picture below?

how come the second man dies?

How do you go from 98 to 720 using just one letter?

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

No matter how little or how much you use me, you change me every month. What am I?