An atomic absorption method for the determination of copper infuels yielded a pooled standard deviation of s-> σ =0.32μg/mL. The analysis of anoil from a reciprocating aircraft engine showed copper content 8.53μg/mL.
(A) Calculate the 95% confidence limits for theresult if it was based upon (a) a single analysis (b) the mean off our analyses,(c) the mean of 16 analyses.
(B) How many replicate measurements are necessary to decrease the 95% and 99% confidence intervals for the analysis to0.2 μg Cu/mL ?