50 Body Weight Squats
40 One arm pull dows, 20 per arm
30 Lying Back Rotations or Standing Rotations
20 Over Head Press
Repeat twice. If you can do more, then the answer is three rounds - again time yourself.
Notes: Body weight squats means just your body (not that you are squating with BW added). On the Rotations, each side counts as 1 and should be done with weight in hands; a medball, kettle bells, or dumbbells will work.