I have a little suggestion:
In the 'Chord inversions' topic 1, you get the bass note as a reference for the chord (for example a G) on which the different
chords are built. So the possible answers would be:
Root: G B D (G chord)
First inversion: G Bb Eb (Eb chord)
Second inversion: G C E (C chord)
But wouldn't it be more useful if you would compare the different inversions of the SAME chord in the exercise?
So for a G chord:
root: G B D
first inversion: B D G
Second inversion: D G B
(But the lowest note changes, which might be the problem)
This way you really get to know how the different inversions of the same chord sound.
I think it would be useful as an option anyway.

Kind regards
Dries