The government has recently introduced a marketable permit program for major polluters where one permit gives permission to pollute one unit. When the program is introduced, Firm A emits 800 units of pollutant and so is granted BUD permits. After one year, rms are issued 209'}.- fewer pollution permits. If Firm A reduces its pollutants from 800 units to 620 units, how man).r permits does it sell after one year