A mechanical engineer who designs and sells equipment that automates manual labor processes is offering a machine/robot combination that will significantly reduce labor costs associated with manufacturing garage-door opener transmitters.

The equipment has a first cost of $170,000, an estimated annual operating cost of $54,000, a maximum useful life of 5 years, and a $20,000 salvage value anytime it is replaced. The existing equipment was purchased 12 years ago for $65,000 and has an annual operating cost of $78,000. At most, the currently owned equipment can be used two more years, at which time it will be auctioned off for an expected amount of $6000, less 33% paid to the company handling the auction. The same scenario will occur if the currently-owned equipment is replaced now. Determine the defender and challenger estimates of P, n, S, and AOC in conducting a replacement analysis today at an interest rate of 20% per year.