What would you do if the you found out you were gonna die in 3 hours?
Invent the time machine. go back in time and talk to my doctor about getting a second opinion. but if it was physically only 3 hours. I would go and hang out with some friends. get incredibly drunk off of some really old single malt whisky (50 years is good). and smoke a nice cuban cigar. hey you only have 3 hours.
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You see a dinosaur running towards you at full pace. you are chained to a wall. there is a camo poop on the ground next to you. What do you do!