Six weeks ago I had a total knee replacement. At this point, what degree or motion should my knee be bending at?

Around 90º-110º. We tell patients based on the worlds literature that your preop motion is the best predictor of your final postop motion. For most people that have "average motion" we tell them that we want them to get full extension and at least 110º of flexion at the final result. Good knees flex between 110º and 130º. The majority of this should be by 6-12 weeks but some improve for much longer.
50 to 60%. Knee replacement sheal about 8 to 10% per week, so at 6 weeks you should be 50 to 60% healed. The best predictor of final range of motion is your original preoperative range of motion.