Create and execute a query that returns the CD titles, their original unit price and then a discounted price (after 20% discount and rounded off to 2 decimal places only) and sort the results with respect to the discounted price. [schema: om]

The query would return 10 rows as shown here

\begin{tabular}{lcc} title & unit_price & afterdiscou \\ \hline Race Car Sounds & 13.00 & 10.40 \\ Rude Noises & 13.00 & 10.40 \\ No Rest For The Weary & 16.95 & 13.56 \\ No Fixed Address & 16.95 & 13.56 \\ Zone Out With Umami & 16.95 & 13.56 \\ Etcetera & 17.00 & 13.60 \\ On The Road With Burt Ruggles & 17.50 & 14.00 \\ Umami In Concert & 17.95 & 14.36 \\ More Songs About Structures and Comestibles & 17.95 & 14.36 \\ Burt Ruggles: An Intimate Portrait & 17.95 & 14.36 \end{tabular}