7.15 A project to extend canals for vegetable crop irri- gation into an area that was recently cleared of Mesquite trees (a nuisance tree in Texas) and large weeds is projected to have a capital cost of $2,000,000. Annual maintenance and operation costs will be $100,000 per year. Annual favorable consequences to the general public of $820,000 per year will be offset to some extent by annual adverse consequences of $400,000 to a portion of the general public. If the project is assumed to have a 20-year life, what is the conventional B/C ratio at an interest rate of 8% per year? ? 7

6. An elective project is currently under review. One alternative requires an initial investment of $116,000 for equipment. The profit is expected to be $28,000 each year, over the 6-year project period. The salvage value of the equipment at the end of the project period is projected to be $22,000. A second alternative requires an initial investment of $60,000 for equipment. The profit is projected to be $16,000 each year, over the 6-year project period. The salvage value of the equipment at the end of the project period is projected to be $14,000. The IRR of this alternative is 18.69%. Determine which alternative is preferred using the appropriate IRR method. Assume a MARR of 10%. Justify your recommendation, based on this method.

4. A city is planning to invest $710,000 for a water treatment plant and need to select projects from the following list. Select any or all of the following independent projects using a MARR of 10% per year (HINT: Calculate PW for all feasible bundles, show PW values for all feasible bundles in the solution and select the bundle). What is the largest PW value? Project Initial Annual cost Salvage Value Life, Investment years 4 A -140,000 -300,000 50,000 45,000 В 90,000 150,000 -10,000 4 -590,000 100,000

2. To reduce flood damage in a river valley in Southern Luzon, a flood control dam is being proposed for construction. The initial cost is estimated to be P4,600,000, with annual maintenance and inspection costs of P24,000. Every 5 years, minor reconstruction work will be undertaken on the dam at a cost of P150,000. If the dam is built, flood damage is expected to be reduced from P800,000 to P100,000 annually. Assuming the dam to be permanent and the interest rate is 8%, should the dam be built?