57. One property of automobile air bags that contributes to their ability to absorb energy is the permeability (ft3

/ft2

/min) of the woven material used to construct the air bags. Understanding how permeability is influenced by various factors is important for increasing the effectiveness of air bags. In one study, the effects of three factors, each at three levels, were studied

(“Analysis of Fabrics used in Passive Restraint Systems—

Airbags,” J. of the Textile Institute, 1996: 554–571):

A (Temperature): 8°C, 50°C, 75°C B (Fabric denier): 420-D, 630-D, 840-D C (Air pressure): 17.2 kPa, 34.4 kPa, 103.4 kPa Analyze this data and state your conclusions (assume that all factors are fixed).