Now Assume that the U.S. worker's wage is still $30 per day and the fixed exchange rate is still $1-110 X (1 Dollar exchanges for 110 Japanese Yen). United States Japan Cars 20 days 20 days Jewelry 10 days 30 days a. If trade is taking place between the two countries, the "lower limit" to Japanese worker's wage per day is Japanese Yen. b. If trade is taking place between the two countries, the "upper limit" to Japanese worker's wage per day is Japanese Yen.