Which u. s. state is the leading producer of christmas trees?

How does specialization enable countries to trade with one another? a country can make and sell goods affordably and buy goods that it is inefficient at making. a country can make what it chooses and sell its goods to other countries. a country can decide to buy everything it needs from other countries. a country can efficiently make goods that were once difficult to make.

Ineed ideas for how to have fun with my friends i feel like they dont like me

What greek scientist created a screw to move water for irrigation?