A man sails off on a cruise between Mexico and the USA. He does not stop at any ports and does not even come out of the cabin, yet he makes $300,000 from his trip.
He's a smuggler.
Bạn thử chứng minh "3n = 4 với mọi n" thử xem nào?
3n = Ba n
4 = Bốn = Bố n