At what interest rate the 5-year Benefit-Cost-Ratio (BCR) becomes unity for an equipment project with the immediate installation cost of -$2500 (in year 0) and a maintenance cost of -$1500 in year 3, and annual benefit of $1000 from the first year onward (n=1 to 5)? Select one: OA. 12.5% O B. 11.5% O C. 14.5% O D. 13.5% OE. 5%