請問CFA L1 book5 Alternative Investment - 金融分析師

請問在Schxxser牌參考書中, book 5的 pg.207中間偏下
有NPV的3個Cash Flow:
year 0: -$370,000
year 1: $39,243 -> After tax cash flow有算出來
year 2: $38,991
year 3: $538,721
CPT-> IRR = 20.18%

請問: y2: $38,991 y3: $538,721是怎麼算出來的呢?

謝謝大家指點~

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