Since the selling price of $585 is marked down by 20%, then, the sale price is
[tex]\begin{gathered} 585-585(0.20)= \\ 585(1-0.20)= \\ 585(0.8) \end{gathered}[/tex]which is equal to $468.
Now, the cost is $360, then the markup is
[tex]468-360[/tex]which is equal to $108. Then, answer is $108.