4. United States income per capita is $50,000. Income per capita for Costa Rica is $10,000. Using what you learned in class, answer the following questions (Hint - the BS effect). State your assumptions clearly and explain your answers! a. In what circumstances is real US income five times greater than Costa Rica? b. In what circumstances is real US income more than five times that for Costa Rica? c. In what circumstances is US real income less than five times that for Costa Rica