Country S is endowed with 1,200 units of labor and can produce two tradable commodities, i.e., clothing and computers. The labor requirement per unit of clothing is 8 and that of computers is 16. Country N is endowed with 800 units of labor and requires 4 units of labor per unit of clothing and 5 units of labor per unit of computers. What is the opportunity cost of clothing in terms of computers for countries S and N, respectively?