Continuing residual income

Question from Schweser: https://ibb.co/hNBad5

Answer: https://ibb.co/jSBad5

I understand all steps except last step. PV of residual incomes in 2019 year end should be 1.59/0.08=19.88. (assuming 1.59 will continue to be constant for infinity)

Well, apart from the fact that bullet point no. 3 in the question actually tells you that the MV at the end of year 3 is 4 times BV. So no need to calculate it yourself