Hello, I would like to ask regarding question number 4 – b from the June 2013 session. I tried to look at the answer of this question, but I couldn`t understand when calculating increase in after tax income – Increase in after-tax income = 576,000 x 0·8 = $460,800 from where 0.8 came? Pls help me to understand from where 0.8 comes. Best wishes, Maria