Notes used in B♭ Dominant 7 Second Inversion Chord:
F + A♭ + B♭ + D
Dominant 7 chords are played combining a root, major third, perfect fifth, and minor (♭) seventh notes of the root note's major scale.
Dominant 7 Second Inversion Chord Formula:
5 + 7♭ + 1 + 3