Perform 40 total reps of the most challenging variation possible, only scaling the movement when completion of 3-4 consecutive reps becomes impossible. Rest as needed, and insist on full range of motion and proper mechanics in each rep.
Then, 10 minutes or 10 rounds, whichever comes first:
30 revolutions Airdyne @ 100%
Score is time to completion (10 rounds) or rounds + reps (10-minute mark). Though output may change, effort should remain at 100%.