Two guys are standing on a rooftop. The first one looked down and asked, "Hey, if I jump down from here, how long do you think it would take me to reach the ground?"
Second one then also looked down and said, "Well, it's pretty high up here. I think it would take at least five days!"
"Really? Okay, here's another one," continues the first. "Do you think if I would die after I jump?"
"Of course you would, five days! How could you survive that long without water?!"