Question

Suppose that a steel manufacturing company wishes to know whether the tensile strength of the steel wire has an overall average of 120 pounds. A sample of 25 units of steel wire produced by the company yields a mean strength of 110pounds and a variance of 144 pounds. Should the company conclude that the strength is not 120 pounds with α=0.05? Obtain a 95% confidence interval for the true mean.​

Answer 1

Answer:

Sublimation is the transition of a substance directly from the solid phase to the gas phase without passing through the intermediate liquid phase (Table 4.8, Fig. 4.2). Sublimation is an endothermic phase transition that occurs at temperatures and pressures below the triple point of a chemical in the phase diagram.