An evacuated thermal insulation is to be designed that will incorporate multiple layers of reflective sheets (ϵ = 0.04) separated by air gap spaces that are partially evacuated and have spacing δ sufficiently small that ke / k =1.0. The insulation is to be designed to operate over a temperature differential from 0oC to 200oC. Investigate the possibilities of using 1, 2, 3, or 4 gap spaces and comment on the influence of different factors on the design, such as gap-space size and the evacuation pressure necessary to produce ke / k = 1.0.