Question: A man obtains a vial of the deadliest venom on earth. A single drop could kill a fully-grown man within seconds. He drinks the entire vial and after a minute, he is not harmed. How did he do it?
Answer: Venom is only dangerous when injected into the bloodstream, not when drunk. Poison is dangerous when drunk. Practically anybody could drink that vial without dying.
Question: There is a 5 gallon and a 3 gallon box. You also have a hose with unlimited water. How are you gonna make the 5 gallon have 4 gallons using your items? (You do not know the exact measure measurements of a gallon)
Answer: You fill the five gallon up and pour it into the 3 gallon. The dump the 3 gallon out and pour what was left in the 5 gallon into the 3 gallon so that you have 2 gallons in the 3 gallon. Then fill the 5 gallon up and pour it into the 3 gallon to fill it up. Now you have 4 gallons in the 5 gallons.