the nation of textilia initially does not allow imports of clothing. in its equilibrium without trade, a t-shirt costs $20, and the equilibrium quantity is 3 million t-shirts. one day, the president decides to open the textilian market to international trade. the market price of a t-shirt falls to the world price of $16. the number of t-shirts consumed in textilia rises to 4 million, while the number of t-shirts produced declines to 1 million