12.27 An engineer at Delphi Systems is considering the projects below, all of which can be considered to last indefinitely. The company's MARR is 13% per year. (a) Determine which projects should be selected on the basis of IROR if the budget limitation is $39,000. (b) What is the overall rate of return if the money not invested in projects is assumed to earn a rate of return equal to the MARR? Problems 337 Net Income, Rate of Project First Cost, $ $ per Year Return, % A -20,000 4,000 20.0 B - 10,000 1,900 19.0 O -15,000 2,600 17.3 D -70,000 10,000 14.3 E -50,000 6,000 12.0