Two Alternative Comparisorn 13. The estimates shown are for a bridge under consideration for a river crossing in Wheeling, West Virginia. Use the B/C ratio method at an interest rate of 6% per year to determine which bridge, if either, should be built East Location West Location Initial cost, S$ Annual M&O, S/year 100,000 Benefits, S/year Disbenefits, S/year Life, years 0000 11 X 106 27 X 106 990,000 20,000 90,000 2,400,000 100,000