11-42. A centrifuge is required in a chemical separation process. Two centrifuges (A and B) are available and summarized below. The net annual revenues for centrifuge B are not known. If the MARR is 10% per year and salvage values can be ignored, what is the minimum value of X to make centrifuge B the better choice? Select the closest answer below.

Year Centrifuge A Centrifuge B 0 −$30,000 −$25,000 1–5 $8,000 $X

(a) $500

(b) $6,700

(c) $8,000

(d) $9,800