You are reevaluating the pump choice that was made last year by your boss. The expected cost savings have not occurred because the pump is too small. Choice A, at $90,000, is to replace the pump with one that is the right size and sell the old one. Choice B, at $100,000, is to buy a small pump to use in tandem with the existing pump. The two-pump solution has slightly higher maintenance costs, but it is more flexible and reliable. What criteria should you use? Which choice would you recommend, and why?