A.Maintenance costs for a small bridge with an expected life of 60 years are estimated to be $1,000 each year for the first five years, followed by a $10,000 expenditure in the 15th year and a $10,000 expenditure in year 30. If interest is 5%  per year, what is the equivalent uniform annual cost over the entire 60-year period?


B.A traffic control system for 40 intersections is based upon central computer control.

The system is estimated to have 20-year useful life and no scrap value. The

cost elements are:

Engineering and field installation:                                               $1.2 Million

Computer facilities:                                                                       $0.3 Million

Communication leases:                                                                 $200,000/year

Maintenance and operation:                                                          $300,000/year

What is annual cost of system? What percent of annual cost is attributed to the

communications expenses? Interest is 5%.