RKI Instruments manufactures a ventilation controller designed for monitoring and controlling carbon monoxide in parking garages, boiler rooms, tunnels, etc. The net cash flow associated with one plant for the first 3 years of operation is shown.

(a) What do the two rules about sign changes indicate concerning i* values?

(b) Find all rate of return values between 0 and 100%.

Year .................................... Net Cash Flow, $
0 ............................................. −30,000
1 ............................................... 20,000
2 ............................................... 15,000
3 ................................................ −2000