(Solved): The void volume within a textile fabric affects comfort, flammability, and insulation properties. P ...

The void volume within a textile fabric affects comfort, flammability, and insulation properties. Permeability of a fabric refers to the accessibility of void space to the flow of a gas or liquid. We have summary information on air permeability (in $${\mathrm{cm}}^3/{\mathrm{cm}}^2/\sec$$ ) for two different types of plain weave fabric (see below). Cotton: $$51.7,49.5,50.3,47.7,47.6,50.2,51.4,55.3,48.8,50.6,49.8,46.2$$ Acetate: $$58.9,55.5,62?1,57.8,60.3,58.6,60.8,58.5,61.2,61.8,64.3,59.5$$ (1) Find a $$90\%$$ confidence interval for the true difference in mean permeability, $${?}_{\text{Acetate }}?{?}_{\text{Cotton }}$$. ) Enter your answers correct to 2 decimal places. (2) What assumptions did you make to answer this question? Do they seem reasonable? Tick all that apply We have two independent random samples of measurements. (Whether this is satisfies depends on the study design.) Standard deviations are equal. (Seems reasonable, from the data.) Data are approximately normal. (Seems reasonable from the normal quantile plot.) Data are approximately normal. (But data are strongly skewed, from the normal quantile plot, so this is not reasonable.) The sample mean difference is approximately normal. (Seems reasonable since $$n\hat{p}(1?\hat{p})>5$$.)