NASA is considering two materials for use in a space vehicle. The costs are shown below. Which should be selected on the basis of a present worth comparison at an interest rate of 4% per year? (40 points) 2. JXMaterial KZ -250,000 -25,000 20,000 4. -210,000 -30,000 First Cost,S Maintenance Cost, S/year Salvage Value, $ Life years 2,000 2