The stepping-stone method is being used to solve a transportation problem. There is only one empty cell having a negative improvement index, and this index is -2. The stepping stone path for the cell indicates that the smallest quantity for the cells with minus signs is 80 units. If the total cost for the current solution is $900, what will the total cost be for the improved solution? What can you conclude about how much the total cost will decrease when developing each new solution for any transportation problem?