1. The estimates shown are for a bridge under consideration for a river crossing. Use the con ventional B/C ratio method at an interest rate of 7% per year to determine which bridge, if either, should be buil East Location West Location 10x10 Initial cost, S Annual M&O, S/year 100.000 Benefits, S/year Disbenefits, S/year, 120,000 Life, yeans 30x106 90,000 2,200,000 100,000 75,000