A contractor estimates maintenance costs for a new backhoe to be $229 for the first month with a monthly increase of 0.5%. If the annual interest rate is 6%. The contractor is planning to sell it after 4 year. What is the present value of the maintenance cost? For the same contractor in question 5 , if it can buy a 4-year maintenance contract with a uniform monthly payment of $323, given the same annual interest rate is 6%, what is the present value of the maintenance contract? For a proposed bridge project, FDOT has estimated the capital investment, annual O\&M cost, net annual benefit, and salvage value under three different scenarios (optimistic, most likely, and pessimistic). Assume the useful life of the bridge is 50 years and the interest rate is 4%, what is the estimated average B/C ratio of the proposed project? Your company is evaluating whether to purchase an equipment or not. The initial cost is $42,713. According to your estimate, the equipment can have annual savings of $6,314 with 0.1 possibility or have annual savings of $5,603. The useful life of the equipment is 10 years, and with equal chance to have a salvage value of $18,771 or $16,566. Given MARR =6%, what is the expected NPV of the equipment? ( 10 points)