Convert CD 74 minutes / 650 MB to zettabit

A CD holds 650 MB of data (74 minutes of audio) or 700 MB (80 minutes). DVDs and Blu-ray discs are sold by nominal capacity: 4.7 GB for a single-layer DVD-5, 8.5 GB for the dual-layer DVD-9, double that for the double-sided DVD-10 and DVD-18, and 25 GB per layer for Blu-ray, so 50 GB for a dual-layer disc. As with hard drives, packaging counts in decimal gigabytes while operating systems display binary ones, so a disc always looks smaller on screen than on the box.