please solve so I can check my work

Problem 2: Below are four mutually exclusive alternatives given in the table below. Assume a life of 7 years and a MARR of 9%. Alt. A Alt. B Alt. C Alt. D - Do Nothing $0 Initial Cost EUAB Salvage Value $5,600 $1,400 $400 $3,400 $1,000 SO $1,200 $400 $0 $0 SO a. The AB /AC ratio for the first increment, (C-D) is how much? b. The AB/AC ratio for the second increment, (B-C) is how much? c. The AB/AC ratio for the third increment, (A-B) is how much? d. The best alternative using B/C ratio analysis is which one and why