What is the EAC for a new bridge that has a first cost of $85M, an annual operating cost of $1.5M, a useful life of 45 years, and an interest rate of 8%? Construct a spider plot and tornado diagram of the EAC of the following conditions

a)First cost ranges between 80% and 140% of base case

b)Annual operating cost ranges between 80% and 120% of base case

c)Interest rate ranges between 75% and 125% of base case