What does this rebus mean?

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What Adam and Eve do not have but the rest of the people have?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Can you complete the sequence?

192, 021, 222, 324, 252, 627, 2__, 9__?

ENEMY = 2 * LINK
LINK + 2 = HELL

Then what will be TAXI + HELL? Select from the options below:
a) ROTTEN
b) DANGER
c) HEAVEN
4) MORTAL

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

If one and a half boys, eat one and a half burgers in one and a half hours.

How many burgers can 9 boys eat in 3 hours?

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.

How many words can a pen with half refill write?

There was a minor accident with a doctor's son but the doctor noticed no major injury. After the treatment, the father of that doctors son is sitting with the son of the doctor without the doctor being in the room.

How can this be possible?