11.4, A dam is to be constructed for flood control. Project costs and benefits vary with the reservoir volume as shown below. Assume a 50-year project life (plan- ning horizon = 50 years) and 4% interest. Reservoir Volume Initial Construction Annual O&M (acre-feet) Costs ($) Costs ($/year) Annual Benefits ($/year) 50,000 4,500,000 A : 32,000 317,000 100,000 5,000,000 A ". 79,000 761,000 150,000 8,000,000 A * 127,000 1,078,000 a. Which dam size will maximize the net present value benefits? b. What is the annualized net benefit of the 150,000 acre-feet project