For its new generation of airplanes, a commercial airline is considering three new designs of the control panel as possible alternatives to the current design with the aim of improving the pilot’s...

For its new generation of airplanes, a commercial airline is considering three new designs of the control panel as possible alternatives to the current design with the aim of improving the pilot’s response time to emergency displays. Letting µ₁
denote the mean pilot response time to simulated emergency conditions with the current design, and µ₂, µ₃, and µ₄
denote the mean response times with the three new designs, write the control versus treatment contrasts.