In a present worth analysis of a certain equipment, one alternative has a net present worth of +$420, based on a 6 year analysis period that equals the useful life of the alternative. A 10% interest rate is used for the analysis.
a) Net present worth: -$420
Analysis period: 4 years
Interest rate: 8%

b) Net present worth: +$350
Analysis period: 8 years
Interest rate: 12%

c) Net present worth: +$500
Analysis period: 5 years
Interest rate: 6%

d) Net present worth: +$420
Analysis period: 6 years
Interest rate: 10%