Here Shelby hurry up so that these point thirsty thieves don't take them;)

Why did china build the great wall of china?

So i need to know the answer to thisi

Without specializing, the total output for both countries after two days would be 48. if country a were to specialize in petroleum, its output would be after two days. if country b were to specialize in seafood, its output would be after two days.