they use some poor language. "High Efficiency" is O3 Low "Low Efficiency" is O3 High They left the "Low efficiency" (O3 High) values as `-` but you can infer

they use some poor language. "High Efficiency" is O3 Low "Low Efficiency" is O3 High They left the "Low efficiency" (O3 High) values as `-` but you can infer them from the plot at the top. Note the $20 and $17 per task aligns with the X-axis of the O3-low