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A permanent flood control dam is expected to have an initial cost of $2.8 million and an annual upkeep cost of $20,000. In addition, minor reconstruction will be required every 5 years at a cost of $200,000. As a result of the dam, flood damage will be reduced by an average of $180,000 per year Using an interest rate of 6% per year, the conventional B/C ratio will be closest to: 0.46 0.81 0.97 1.06