For 50 Points
A worker is wearing a fall arrest system with a 6-foot lanyard. The lanyard is attached to the D-ring on the back of his harness. This D-ring is 5 feet above the sole of the person’s foot when he is standing. There is 4 feet of deceleration-induced lanyard stretch during a fall. For this setup to be safe, how high must the anchor point be above the surface onto which a worker might fall?