10-10. In the development of a publicly owned, commercial waterfront area, three possible independent plans are being considered. Their costs and estimated benefits are as follows: (10.8) PW ($000s) Plan Costs Benefits A $123,000 $139,000 B 135,000 150,000 C 99,000 114,000

a. Which plan(s) should be adopted, if any, if the controlling board wishes to invest any amount required, provided that the B–C ratio on the required investment is at least 1.0?

b. Suppose that 10% of the costs of each plan are reclassified as disbenefits. What percentage change in the B–C ratio of each plan results from the reclassification?

c. Comment on why the rank-orderings in

(a) are unaffected by the change in (b).