Answer: Building C
Explanation:
We will take out the present value of each of the alternative
A: PV = $610000
B: PV = 70000 + 70000×(P/A,12%,24) = 614902
Where, [P/A, r %, n] = [((1+r)^n -1)/(r(1+r)^n]
r=12%=12/100=0.12 ; n=24
70000 + 70000 * [((1+0.12)^24 -1)/(0.12(1+0.12)^24]
= $614902
C: PV = 650000- 6000×(P/A,12%,25) = 602941
recall, [P/A, r %, n] = [((1+r)^n -1)/(r(1+r)^n]
r=12%=12/100=0.12 ; n=25
650000 - 6000 * [((1+0.12)^25 -1)/(0.12(1+0.12)^25]
= $602941
Thus, the minimum will be selected, that is building C