please do excel and use formulas

In order to improve evacuation routes out of New Orleans in the event of another major disaster such as Hurricane Katrina, the Louisiana Department of Transportation (L-DoT) is planning to construct an additional bridge across the Mississippi River. The department uses an interest rate of 8% and plans a 50 -year life for either bridge. Which design has the better present worth? Contributed by Pail R. McCright, University of South Florida