18. Consider the difference between the implications of the standard trade model and the outcome of international trade in the presence of external economies of scale. Which of the following outcomes below is valid the standard trade model for but not valid for international trade in the presence of external economies of scale? (i) international trade has a predictable pattern (il) world production is concentrated in a single location (iii) relative prices converge in different countries (tv) the effect of trade is to reduce prices everywhere a b. (1) and (ii) C. (i) and (hii) (i), (ii), and (iv)