The answers are displayed in the boxes, I just do not understand how they obtained the solutions.

The two mutually exclusive alternatives shown in the table are available (do nothing" (DN) is also an option). If the MARR = 11% select the better alternative with an incremental analysis using the IRR method. Given: IRRA-20.6% and IRRB-14.4%. Assume repeatability Initial cost Salvage value Cash flow (annual) Life (years) -$10,000 500 3,000 6 $6,000 2,600 Which alternative would you choose as a base one? Choose the correct answer below XA. Alternative A B. Alternative B C. Doing nothing Analyze the difference between the base alternative and the second-choice alternative IRR ( B -DN ) = 14.496. (Round to one decimal place.) Analyze the difference between the current base alternative and the third-choice alternative IRR ( A -B ) is 28.8%. (Round to one decimal place.) Which alternative should be selected? Choose the correct answer below XA. Alternative B B. Doing nothing C. Alternative A