For various flood risks expressed by the expected return periods at a given location, the damage costs and the annualized capital costs of reservoir designed to control the floods, are shown in Table 1 [100] a) Determine the expected annual damages if no structure is provided, b) Calculate the optimal design return period, c) Determine the reservoir capital cost, damage risk cost, and the total cost for the optimal d) Do you believe that the reservoir flood storage capacity that minimizes total cost (flood damage plus capital cost) is the best option for local residents? Please leave a comment.

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