Final answer:
A Perfect Fifth above D-flat is Ab.
Step-by-step explanation:
A Perfect Fifth is an interval between two pitches that is five diatonic scale degrees apart. To determine a Perfect Fifth above D-flat, we need to count up five diatonic scale degrees from D-flat. The diatonic scale of D-flat major consists of the notes Db, Eb, F, Gb, Ab, Bb, and C. Counting up five scale degrees, we arrive at the note Ab. Therefore, a Perfect Fifth above D-flat is Ab.