问题如下：
Wilson Flannery is concerned that this project has multiple IRRs.
How many discount rates produce a zero NPV for this project?
选项：
A.One, a discount rate of 0 percent.
B.Two, discount rates of 0 percent and 32 percent.
C.Two, discount rates of 0 percent and 62 percent.
解释：
C is correct.
使用试错法，将选项代入计算 NPV：代入 32%，NPV = 4.018143；代入 62%，NPV = -0.032083。
62% 计算出的 NPV 近似为 0，所以选 C
请问第三年-50，带入-50吗？62是直接输入在I里面吗？
