Write out the V7 chord (simple root position, any clef) in all minor keys; use the key signature for each key.

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A dominant chord is a major triad built on the fifth scale degree of either a major scale or a minor scale. Major triads consist of a root note, a major third, and a perfect fifth. ... A simple D major triad contains the notes D, F♯, and A. This chord becomes a dominant seventh chord (V7) by adding the note C.