Workers will be using stilts that are 24 inches tall to reach structural beams/ceiling above a third story floor. The walls have not been erected and thus a leading edge is present. A guardrail system has been selected to be used for fall protection. What height should the top rail of the system be set at? 42 inches plus or minus 3 inches above the w/w surface 66 inches plus or minus 3 inches above the w/w surface 74 inches plus or minus 3 inches above the w/w surface 39 inches plus or minus 3 inches above the w/w surface