Hi, I calculate the IRR using excel spreadsheet and the function called IRR(). A, I calculate Project As IRR as 34.903%, and Project B as 31.607%. B, for Project A, when discount rate is 0, present value is 4000-2000=2000, when discount rate is 5%, present value is 3545.95-2000=1545.950504, when discount rate is 10%, present value is 3169.87-2000=1169.865446, when discount rate is 20%, present value is 2588.73-2000=588.7345679. For project B , when discount rate is 0, present value is 6000-2000=4000, when discount rate is 5%, present value is 6000/(1+0.05)^4-2000=4936.214849-2000=2936.214849, when discount rate is 10%, present value is 6000/(1+0.1)^4-2000=4098.080732-2000=2098.080732, for discount rate of 20%, present value is 6000/(1+0.2)^4-2000=893.5185185 C. In term of the optimal choice, the rule of thumb is the project with the highest IRR is the best because it has a higher potential. In the regard, Project A is comparably better. When WACC reachs as high as 33%, Project A can still has a positive present value, whereas project B can not. But it is also worth noticing that in every level under 31.607%, Project B beat Project A. So in conclusion, Project A has higher potential, when Project B has better yield. 如果你對我的回復滿意，麻煩給一個五星評價