The fingerboard options.
The settings above are a great place to start. If it's a little to hard or too easy adjust the time. When you get better throw in sharps and flats. When you have sharps and flats mastered then make it harder by turning off the text hint. That will remove the crutch of seeing the note name along with the note on the staff.
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The fingerboard options set you vary the level of difficulty in your exercise.