A new storm drainage system must be constructed right away to reduce periodic flooding that occurs in a city that is in a valley. Five mutually exclusive designs have been proposed, and their present worth (in thousands of dollars) of costs and benefits are the following:
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_________________________System__________________
__________________1_______2_______3________4_______5
PW of costs______ $1000__ $4000____$4000 ____$10000 __$12000
Pw of benefits______8000___8000_____14000_____16000___24000
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a. Which system has the greatest B-C ration?
b. Which system has the largest incremental B-C ratio (based on differences between alternatives)?
c. Which system should be chosen?