The cash flow of an energy management opportunity is estimated as follow: Initial cost: $12,000 Energy saving: $2,700/year for 12 years Maintenance cost: $1,200/year for 12 years Salvage value: $2,500@ the end of 12 years If the interest rate is 10%, 1) What is the simple payback period (SPP) (in years)? (a) 5.2 (b) 4.2 (C) 4.6 (d) 8.0 (e) 5.0 2) With an annual discount rate is 10%, what is the discounted payback period (in years)? (a) 9.5 I (b) 15.1 (e) 8.1 (d) 16.9 (e) 6.5 3) With an annual discount rate is 10%, what is the benefit-cost ratio (BCR)? (Hint: Benefit = Annual saving - Maintenance; Cost = Initial investment - Salvage) (a) 1.04 (b) 0.80 (c) 1.25 (d) 1.12 (e) 1.43